Monday, May 18, 2026

Slav Defence - Summary

 Christer Sundqvist: New ideas in the Slav Defence

This is an overview of a comprehensive analysis package that includes the Slav Defence. I'd like to show you a typical line of play in order to pique your interest in this rapidly changing chess opening.

With a small investment on your part, I can send the entire package (48 PGN files!) to your email address. I use this blog to help me deal with the massive number of draws in correspondence chess. I'm only doing this for fun, not for money. I also provide you with regular updates at no additional charge. I use PayPal, MobilePay, and traditional IBAN bank transfers. Please let me know how you want to receive the chess opening package. My email address is turpaduunari@outlook.com. Chess players interested in my chess databases have typically paid between 30-150 euros per database.

If you believe my request for money is unethical or greedy, I am willing to consider alternative solutions (exchange of valuable ideas or other forms of collaboration).


I have used these resources:

  • Batsford's Modern Chess Openings (15th edition) = MCO

  • Chess Cloud Database Query Mode (https://www.chessdb.cn/queryc_en/) = CCD

  • Chess Informant 147, 152, 166

  • Chessbase software

  • Alexey Dreev. The Moscow & Anti-Moscow Variations. Chess Stars, 2011

  • ICCF Games Archive (https://www.iccf.com/message?message=454 ) 1961–2026

  • Opening Master Chess Database (https://www.openingmaster.com/)

  • Bryan Paulsen. Chess Developments: Semi-Slav 5 Bg5. Everyman Chess, 2013

  • Personal chess database (approx. 90 million games)

  • Sam Shankland. Lifetime Repertoire: Semi-Slav. Chessable, 2021

  • Stockfish 18 chess engine

  • Sundqvist, Christer. The Slav Defense played by a strong correspondence chess player 2019-2026

  • The Week in Chess (https://theweekinchess.com/twic ) 1994–2026

  • James Vigus. Play the Slav. Everyman Chess, 2008.

  1. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.Bg5
  2. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.Nf3
  3. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Bf5
  4. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Nc6 6.Nf3
  5. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Nc6 6.e3
  6. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Nc6 6.other
  7. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 Qb6
  8. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bf4 other
  9. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.Bg5
  10. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.f3
  11. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 cxd5 5.other
  12. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.cxd5 other
  13. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.e3
  14. 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.other
  15. 1.d4 d5 2.c4 c6 3.Nc3 e6 4.e3
  16. 1.d4 d5 2.c4 c6 3.Nc3 e6 4.e4
  17. 1.d4 d5 2.c4 c6 3.Nc3 e6 4.other
  18. 1.d4 d5 2.c4 c6 3.Nc3 other
  19. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 a6
  20. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 dxc4
  21. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 Be7
  22. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 Nbd7
  23. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 dxc4
  24. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bxc6
  25. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 other
  26. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.e3
  27. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.g3
  28. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.other
  29. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 other
  30. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.e3
  31. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.other
  32. 1.d4 d5 2.c4 c6 3.Nf3 e6
  33. 1.d4 d5 2.c4 c6 3.Nf3 other
  34. 1.d4 d5 2.c4 c6 3.cxd5
  35. 1.d4 d5 2.c4 c6 3.e3
  36. 1.d4 d5 2.c4 c6 3.g3
  37. 1.d4 d5 2.c4 c6 3.other
  38. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 Be7
  39. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.Be2 Bb7 10.0-0
  40. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.Be2 Bb7 10.Qc2
  41. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.Be2 Bb7 10.h4
  42. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.Be2 other
  43. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.Ne5
  44. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.h4
  45. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 g5 8.Bg3 b5 9.other
  46. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.e4 other
  47. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 dxc4 7.other
  48. 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 h6 6.Bh4 other


1.d4 d5 2.c4 c6

The Slav Defence is Black's most obvious strong response to the Queen's Gambit. It strengthens the d5-pawn while allowing the queen's bishop to enter the game, unlike the Queen's Gambit Declined (2...e6). True, it deprives the queen's knight of its supposedly most active square, but this piece is usually assigned to d7 in most Queen's Gambit structures. 2...c6 is not just a defensive move; it also creates a threat. A subsequent...dxc4 can now be reinforced with...b5, requiring White to decide whether to make his Queen's Gambit a true gambit or not.


3.Nf3

This is White's most common move.


3...Nf6 4.Nc3

4. Bf4 dxc4 is almost never effective with c4 against the Semi-Slav repertoire. White should stick to either the London or the Semi-Slav, but not both. Black takes the pawn and gets away with it, easily completing his development with e6, Be7, b5, Bb7, and so on, remaining a pawn ahead.


4...e6 5.Bg5

5.e3



This move (5.e3) is very popular, but it's pretty drawish, and I don't like blocking the diagonal c1–h6. Analyses of the e3-move are available elsewhere in my collections. Move 5. Bg5 indicates that White is putting up a serious fight.


5...h6 6.Bh4



The Anti-Moscow Variation (6. Bh4) is an authentic gambit in every sense of the term. White offers the c-pawn in exchange for faster development and is exposing some weaknesses in Black's structure. The play is frequently very sharp, and correspondence chess games usually have the final say. This is currently the situation in very sharp positions. Needless to say, OTB players would benefit from studying the lines of play outlined in this summary.

6. Bxf6 represents the Moscow variation. It is thoroughly examined elsewhere in my chess databases.


6...dxc4

Black has won his pawn and will ensure that he keeps it in the following moves.


7.e4



The principled reaction to Black surrendering the center, as well as the move the Queen's Gambit Accepted would prefer to see (compare 1 d4 d5 2 c4 dxc4 3 e4).


7...g5

The distinguishing feature of the entire complex. Black is content to have a weakened structure in exchange for the ability to reinforce c4.


8.Bg3 b5

Black has complete ownership of his extra pawn, and White must now find a way to cause problems for Black.


9.Be2

The most common and simple move to discover. Instead of attempting to initiate immediate complications, White simply develops.


9...Bb7



After some trial and error in which Black received some brutal practical and theoretical beatings in other continuations, it was determined that this unassuming continuation was his best option. This is the move I would recommend!


10.0–0

White responds in the most natural way.

10.e5



This is an alternative position in the Anti-Moscow variation. However, White should proceed with caution!

A) 10...Nd5

A1) 11.0–0 Qb6 12.Nxd5 cxd5 13.Ne1 Nc6 14.Nc2 0–0–0 (14...b4!) 15.Bh5 Rh7 16.Kh1 b4 17.b3 Ba6! Black is better 18.f4 cxb3 19.axb3 Bxf1 ½–½ (58) Williams,S (2443)-De Vleeschauwer,M (2277) Reykjavik 2026;

A2) 11.h4?!

A2a) 11...g4 12.Nd2 h5 (12...Nxc3!) 13.Nde4 Nd7 14.0–0 Qb6 15.a4 a6 16.Ng5 c5!



Black seizes the initiative with this move. 17.axb5 axb5 18.Rxa8+ Bxa8 0–1 (30) Novikov,M (2500)-Zaitsev,A (2408) Tula 2014;

A2b) 11...Qa5 12.Rc1 (12.hxg5 Nxc3 13.bxc3 Qxc3+ 14.Kf1 Na6!? 15.g6!? 0–0–0 16.gxf7 Bg7) 12...g4 13.Nd2 c5! 14.Nce4 cxd4 15.0–0 Nc6!



Although the position is equal, Black has better chances.

B) 10...Nh5



This move is advantageous from a positional standpoint, as Black wishes to exchange his knight for White's bishop.

11.a4! a6 12.Nxg5! Nxg3 13.Nxf7 Kxf7 14.fxg3 Kg8! 15.0–0 Nd7 16.Bg4 Qe7 17.Ne4 Rh7?! (17...c5! 18.Rf6! Bd5 19.Rg6+ Kh7 The position is equal) 18.Nd6 Kramnik! 18...Rb8 19.axb5! cxb5 20.Nxb7 Rxb7 21.Rxa6 Rb6 22.Rxb6 Nxb6 23.Rf6 Kh8 24.Bxe6! Bg7 25.Rg6 White is better]


10...Nbd7 11.Ne5


White chooses active piece play, believing Black's loosened structure to be sufficient without the provocation of h2-h4. This move exemplifies White's choice of the Modern system. The positions in the Anti-Moscow variation are so complicated that a final decision will not be made anytime soon.


11...Bg7

This is the conservative choice.

11...h5



The theory of the line with 11...h5 has not yet been fully developed, so there are numerous opportunities for new ideas. 12.Nxd7 Qxd7 13.Qc1!? Rg8 14.Rd1 (14.Qe3 h4 15.Be5 Qd8 16.h3 Nd7 17.Bh2 Qb6 18.Rfd1 e5 19.Bg4 Rd8 20.Qf3 exd4 21.e5 c5 22.Ne4 Bxe4 23.Qxe4 Be7 24.a4 b4 25.Qe2 d3 Black is slightly better, but blunders badly in the endgame. 1–0 (39) Erdogmus,Y (2687)-Topalov,V (2717) Monaco 2026)

A) 14...a6 15.Qe3 (15.b3 cxb3 16.axb3 Bb4 17.Na2 Be7 18.Qe3 Qc8 ½–½ (44) Bontems,C (2275)-Sundqvist,C (2359) ICCF 2022; 15.h3 g4 16.h4 Bb4 17.Qf4 Rg6 18.a4 Rd8 19.Qe3 Qe7 20.Bf4 Nd7 21.Qg3 Nf6 22.Qe3 Nd7 23.Bg3 Nf6 24.Bf4 Nd7 25.Qg3 Nf6 26.Qe3 Nd7 ½–½ (26) Javier,G (2315)-Glørstad,T (2388) ICCF 2024; 15.a4 Rg6 16.h3 g4 17.h4 Bb4 ½–½ (17) Sundqvist,C (2247)-Osorio,J (2385) LSS 2024) 15...Ng4 16.Bxg4 hxg4 17.b3 cxb3 18.axb3 Be7 19.f3 gxf3 20.Qxf3 Rh8 21.Rac1 Rh6 22.h3 Rc8 23.Kh2 f6 24.Rd3 Rd8 25.Qe2 Ba3 ½–½ (49) Dutra,A (2452)-Kudr,R (2452) ICCF 2025;

B) 14...Bb4!? 15.Qc2 h4 16.Be5 Qe7 17.h3 a6 18.a4 g4 19.Bxf6 Qxf6 20.Bxg4 0–0–0 21.e5 Qf4 22.Ne2 Qh6 23.Bf3 f5 24.b3 c5 25.d5 Rxd5 26.Rxd5 Bxd5 27.Bxd5 exd5 28.Qxf5+ Kb8 29.axb5 cxb3 30.Rxa6 Qg5 31.Rb6+ Ka8 ½–½ (31) Lopez,H (2335)-Garau,B (2335) ICCF 2025;

C) 14...h4 15.Be5 Qe7 16.h3 g4 17.Bxf6 Qxf6 18.e5 Qh6 19.Qxh6 Bxh6 20.hxg4 0–0–0 21.Ne4 Bf8 22.b3 Ba3 23.bxc4 bxc4 24.Rab1 Ba6 25.Kh2 Rh8 ½–½ (47) Boyd,J (2259)-Sharpe,S (2399) ICCF 2025]


12.Nxd7

Black is forced to place a piece on d7, which disrupts his coordination, but the answer to the question "which piece?" has been known for quite some time.

12.Nxf7!?



This Knight-sacrifice was first tried in the well-known game Topalov-Kramnik, Wijk aan Zee 2008. Black did not defend precisely in it, so White took the initiative and won spectacularly. Shortly thereafter, Black's game improved. The theory of this variation continues to evolve, but White's enthusiasm has waned significantly, as it appears that Black has more than enough counterarguments.

12...Kxf7 13.e5 Nd5

A) 14.Ne4 Ke7 15.Nd6 Qb6

This is Black's most logical and natural move.

16.Bg4



This is a tremendously complicated position!

16...h5 Karjakin played this move in his game against Shirov (Foros 2008). (Dreev) (16...Raf8 17.Qc2 Rhg8 18.Qg6 Nc7 19.Qe4 Kd8 20.f4 Ba8

This setup is effectively bulletproof, and some brief tactical complications have emerged.

21.fxg5 hxg5 22.Rad1 c5! 23.Qh7 cxd4 24.Rxf8+ Rxf8 25.Qxg7 d3+ 26.Kh1 Qe3



The white king has the same problems as his opposing majesty, and in a recent correspondence game, the opponents agreed to a draw after:

27.Nf7+ Kc8 28.Nd6+ Kd8 due to the repetition.) 17.Bxh5 Raf8 18.Qg4 Bh6 19.a4 (19.h4 c5!? 20.hxg5 Bg7 21.g6 Kd8 22.a4 cxd4 23.axb5 Nxe5 24.Bxe5 Bxe5 25.Nxc4 Bh2+! equal position) 19...Nf4 20.Qd1 Bg7 21.Bf3 c5 22.Nxb7 cxd4 23.axb5 Nxe5 24.Kh1 Rc8 25.Qa4 Nxf3 26.Qa3+ Kd7 ½–½ (53) Dzenis,J (2289)-Guelfi,L (2252) ICCF 2025;

B) 14.Bh5+ Ke7 15.Nxd5+ cxd5 16.f4 Qb6 17.fxg5 Raf8 18.gxh6 Bxe5 19.Bxe5 Nxe5 20.Qd2 Nd7 21.Rxf8 Rxf8 22.Rf1 Rxf1+ 23.Kxf1 Nf6 24.Bg6 b4 25.h7 Ba6 26.Ke1 Nxh7 27.Bxh7 e5 28.Qg5+ Qf6 ½–½ (28) Nett,P (2223)-Jung,R (2289) ICCF 2024


12...Nxd7


The safest capture, keeping White from attempting a quick e4-e5 with Ne4-d6.


13.Bd6

White denies Black the luxury of castling.


13...a6!

White faces a difficult task in improving his position. If White plays too slowly, Black is ready to free his position.


14.a4



The most direct threat to Black's opening with 11...Bg7


14...b4

This is the move made in the game Topalov-Gelfand, and it is likely Black's best attempt in the main line of the Anti-Moscow Gambit. I've tried it several times in my correspondence games, and precise play results in a draw.

14...e5



This move was made in Anand-Leko (2009), and some consider it a draw with perfect defense, but I am not sure. I believe White is better.

15.Bg4!?

A) 15...exd4 16.e5 c5 17.Re1 This is considered to be the best move for White. 17...Nxe5! 18.Bxe5 0–0 19.Bxg7 Kxg7 20.Ne2

A1) 20...f5 21.Bh5 f4 22.Nxd4!? cxd4 23.Re6 Rf6



Anand-Leko continued 23...Bc8. The evaluation of this position is critical for the overall variation with 14.a4. If White maintains the advantage, Black must find additional resources in this line or pay more attention to the variation with 11...h5. It appears that he holds, but the position is so complicated for an analysis that drawing any conclusions would be premature.

(23...Bc8 24.Rg6+ Kh7 25.axb5 Rf6 26.Rxf6 Qxf6 1–0 (45) Anand,V (2788)-Leko,P (2752) Moscow 2009) 24.Qe1 Bd5 25.Re7+ Kg8;

A2) 20...Qf6 21.h3 Be4 22.f4 gxf4 23.Rf1 Qe5 24.Nxf4 f5 25.Bh5 Kg8 1–0 (48) Tudor,V (2159)-Rheindt,S (2119) ICCF 2025;

B) 15...b4 16.Ne2 Nf6 17.Bxe5 0–0 18.Ng3 c5 19.Rc1 Nxe4 20.Bxg7 Kxg7 21.Nf5+ Kh8 22.f3 Nd6 23.dxc5 Nxf5 24.Bxf5 Qf6 25.Bb1 Rfd8 ½–½ (35) Detchin,Y (2391)-Timofeev,A (2390) ICCF 2024


15.Bxb4

15.d5



Due to the complexity, OTB games are rarely seen, and disputes are now almost exclusively resolved through correspondence games. It is extremely easy to make major mistakes.

A) 15...Ne5 16.dxe6 bxc3 17.Bh5

A1) 17...Qf6?? 18.Bxe5 1–0 (18) Csonka,B (2494)-Deac,B (2683) Chess.com INT 2022;

A2) 17...Bc8?! 18.exf7+ Nxf7 19.e5 Be6 20.bxc3 Bf8 21.Re1 Qd7 22.Rb1?! (22.Qb1!? Be7 23.Rd1 Bd5 24.Bxe7 Qxe7 25.e6 Bxe6 ½–½ (38) Galanov,S (2539)-De Oliveira,M (2507) ICCF email 2013) 22...Be7 23.Qc2 Kf8 ½–½ (36) Cheparinov,I (2687)-Sakaev,K (2596) Moscow 2019;

A3) 17...c2 18.Qd4 Rf8 19.Qc5 Qf6 20.Qb6 Qxe6 21.Bxf8 Kxf8 22.Qxb7 Re8 23.Rac1 Nd3 24.Rxc2 Nf4 25.Qxf7+ Qxf7 26.Bxf7 Kxf7 ½–½ (43) Dziedzic,A (2364)-Wade,W (2366) ICCF 2025;

B) 15...exd5 16.exd5 bxc3 17.dxc6 Bxc6 18.bxc3 Ne5 19.Re1 (19.Qd4 Qa5 20.Rfd1 Rc8 21.Bb4 Qd8 22.Qe3 Qf6 23.Bg4 Rb8 24.Bd6 Rd8 25.Bxe5 Rxd1+ 26.Rxd1 Qxe5 ½–½ (39) Guelfi,L (2260)-Pérez López,A (2471) ICCF 2025) 19...Ra7 20.Bxc4 (20.Bxe5?! Bxe5 21.Bf3 Qf6 22.Bxc6+ Kf8 23.Rc1 Kg7 24.Qf3 Rd8 25.g3 Rc7 ½–½ (32) Fedoseev,V (2674)-Bukavshin,I (2618) Moscow 2015) 20...Re7 ½–½ (20) TeVrucht,R (2108)-Scarabeli Candido,R (1892) ICCF 2025 21.Qd4 Nf3+ 22.gxf3 Bxd4 23.Bxe7 Qd7 24.Bc5+ Kd8 25.Bxd4 Bxf3 ½–½ (40) Rodriguez Zas,J (2349)-Dillenburg,A (2344) ICCF 2025]


15...Qb6 16.Ba3 Qxd4 17.Qc2

17.a5



a pretty drawish line

17...Qxd1 18.Rfxd1 c5 19.Bxc4 Bxc3 20.bxc3 Bxe4 21.Rd6 (21.f3 Bb7 22.Bc1 Ke7 23.f4 Rhg8 24.fxg5 Ne5 25.Be2 hxg5 26.Be3 Nd7 27.Rd2 Bd5 28.Rad1 Ra7 29.Bf2 ½–½ (29) Ilchen,H (2157)-Sparnacini,S (2183) ICCF 2025) 21...0–0–0 22.Rxa6 Kc7 23.Ra7+ Kb8 ½–½ (23) Nowak,I (2037)-Sundqvist,C (2225) LSS 2022 and ½–½ (25) Szerlak,A (2416)-Postupa,P (2469) ICCF 2025; 17.Qxd4 Bxd4 18.Bxc4 Ne5 19.Be2 c5 20.Rfd1 0–0 21.Rac1 Rfd8 22.Kf1 Bc6 23.b4 Bxc3 24.Rxd8+ Rxd8 25.Rxc3 cxb4 ½–½ (25) Oliveira,M (2519)-Sýkora,J (2505) ICCF 2024


17...c5

17...Qb6 18.a5 Qc7 19.Na4 c5 20.Qxc4 0–0 21.Nb6 Nxb6 22.axb6 Qc6 23.Qxc5 Qxc5 24.Bxc5 Rfd8 25.Rfe1 Bxb2 ½–½ (59) Rodríguez Zas,J (2355)-Hernández Martínez,J (2389) ICCF 2025


18.Rad1

18.Rfd1 Qe5 19.Bxc4 Qc7 20.Ne2 Be5 21.Ng3 h5 22.Nf1 g4 23.Rac1 h4 24.b4 g3 25.bxc5 Bc6 ½–½ (35) Rodríguez Zas,J (2361)-Razumikhin,A (2427) ICCF 2025


18...Qe5 19.Bxc4 Qc7 20.Ne2 0–0

20...Be5 21.Kh1 Rd8 22.b3 g4 23.Qd3 Nb6 24.Qe3 Nxc4 25.bxc4 Rxd1 26.Rxd1 Qc6 ½–½ (45) Suihko,K (2430)-Broniek,M (2497) ICCF 2025


21.Ng3 Ne5

21...Rfd8



22.Be2 (22.b3 Ne5 23.Be2 c4 24.Bb2 c3 25.Rxd8+ Rxd8 26.Rc1 Rc8 27.Qxc3 ½–½ (27) Shabaev,V (2113)-Sundqvist,C (2241) ICCF 2020) 22...Rac8 23.b3 Bd4 24.Kh1 Nf8 25.Nh5 Ng6 ½–½ (54) Rodriguez Zas,J (2355)-Debnár,I (2288) ICCF 2025


22.Be2 Ng6

22...Rac8 23.Nh5 Bh8 24.f4 Ng6 25.f5 exf5 26.Rxf5 Rfe8 ½–½ (31) Mroczek,J (2334)-Esquivel León,J (2271) ICCF 2025


23.Rc1



23...Rfc8 24.Bxc5 Nf4 25.b4 a5 26.Bb5 axb4 27.Qb1 Qe5 28.Bxb4 h5 29.Rxc8+ Rxc8 30.Rd1 h4 31.Bd6 Qb2 32.Qxb2

½–½ (32) Oliveira,M (2443)-Sundqvist,C (2473) ICCF 2024


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Wednesday, April 29, 2026

Is chess a draw? Yes, but finding it is the real skill!

With perfect play, chess is a draw

Most chess players are familiar with the famous hypothesis: if both sides play perfectly, the starting position is a draw. Nobody has proven this. The game tree is too extensive. However, Grandmaster practice and engine analysis strongly suggest it is true.

For years, I treated this as a fascinating piece of trivia. Today, at 2518 ICCF, I understand something I didn't know at 2200. The "draw by perfect play" hypothesis is not trivial. It is the theoretical basis for every difficult defensive and offensive task I face in chess. If chess was a theoretical victory for White, defending as Black would be a slow death march. But, because chess is almost always a draw, every position I defend has a path back to equality - sometimes narrow, sometimes nearly invisible.


Why is it important now?

In one of my current correspondence games, I need to find a draw before my opponent wins. The position remained balanced for the first 12 moves. 

Then I moved g7-g6 instead of b7-b6, and my opponent's response caused the engine evaluation of my position to drop by 2.9, which is a significant amount. In a matter of seconds, I converted a theoretical draw into a near-certain loss. And I have the horrendous task of finding a continuation that leads to equality. The engine gives my opponent a clear winning path - if I cannot find the single defensive move that holds. I'd rather not post the actual positions in an unfinished chess game, but I will publish the game once it's completed.

Correspondence chess allows you to use every possible aid (chess books, chess databases, engines, and so on) to help you make moves. I don't always use computers to play correspondence chess. I understand that at 2500+ ICCF, this may be unusual. Most of my opponents have engines running alongside every move, analyzing at a level that I cannot match. But I've always believed that relying too heavily on the computer impairs your own chess judgment. Sometimes you have to believe your instincts.

Your instincts can sometimes betray you. In one natural-looking move, I transformed a drawn position into a nearly certain loss. And because this is correspondence chess, my opponent has several months to find the moves that will lead to a decisive victory. He will eventually find it. If I don't come up with a draw before he wins me.

That's the distinction between knowing chess is a draw and finding it when it counts. I was familiar with the theory. Instead of trusting the machine, I went with my gut. And I'm now paying the price.


What's coming next?

In the coming weeks, I'll talk about correspondence chess, the tools we have to make our moves, the search for the perfect chess move, and how correspondence chess can help us develop chess opening theory. Over the next few posts, I'll explain what I've learned about reading chess engine evaluations. I will guide you down the narrow path of determining the one move that holds a draw when everything else fails. I'll explain what happens when tablebases tell you the truth. When seven-piece endgames transform speculation into certainty. You'll find real games, real decisions, and annotated positions from my own ICCF experience. Much of the theoretical issues stem from discussions on a national chess forum and a lecture I gave on the pursuit of the perfect move in chess.

A hard-fought draw in over-the-board chess can feel like securing half a point. A hard-fought draw in correspondence chess feels like a small proof. Not a proof that chess is a draw - that remains a conjecture. But a proof that this opponent, this game, could not be won.

BTW, we have played one move each since the catastrophic incident. The engine evaluation remains unchanged. At least the situation has not gotten worse.

Follow the story

This game isn't over. Whether I find the draw or spiral into a crushing loss, I'll document everything - the engine checks, the late-night second-guessing, the moment my opponent finally strikes (or fails to).

If you want to follow along:

  • Bookmark this blog and check back in a few weeks
  • Reply or comment with your own correspondence chess disasters - misery loves company
  • Send messages to me using the simple "Please Contact Me Here" - option in the right column


Once the game finishes, I'll publish the fully annotated game: the position I couldn't show you, the engine's cold judgment, and whether I managed to prove that -2.9 wasn't the end.

The story continues.


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Saturday, April 11, 2026

My huge chess opening databases have been updated

 

Chess databases / update packages 11042026

Those who would like to be included in the update cycle should contact me. Users paid anywhere from 0 to 150 euros for the updated packages. Rather than sending money, they sent me a variety of chess items. Although I prefer money, I am not a greedy person. The chess opening files are enormous and will undoubtedly help you understand chess better.

Enjoy! 

Contact: turpaduunari@outlook.com 

IM Christer Sundqvist




  • The f3-Nimzo-Indian defence

  • The Sicilian Najdorf

  • Queen's Gambit Accepted

  • King's Indian Defense

  • Caro-Kann Defense - Finnish variation

  • Halloween Gambit

  • Benko Gambit

  • Grünfeld Defense

  • Dragon Sicilian


Schedule Aug-2025 / Oct-2025 / Dec-2025 / Feb-2026 / Apr-2026 / Jun-2026 / Aug-2026 / Oct-2026 / Dec-2026


The f3-Nimzo-Indian defence


  1. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 0-0

  2. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 0-0

  3. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 b5

  4. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 0-0

  5. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd2 Bxc3

  6. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd2 a6 8.a4 bxc4

  7. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd2 a6 8.a4 exd5

  8. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd2 a6 8.a4 other

  9. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd2 a6 8.other

  10. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd2 other

  11. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Bd3

  12. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.Nge2

  13. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.a3 Bxc3+

  14. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.a3 other

  15. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.dxe6

  16. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 b5 7.other

  17. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.e4 other

  18. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 d6 6.other

  19. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.d5 other

  20. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 c5 5.other

  21. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Be7

  22. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Bxc3+ 6.bxc3 0-0

  23. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Bxc3+ 6.bxc3 c5 7.cxd5 Nxd5

  24. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Bxc3+ 6.bxc3 c5 7.cxd5 exd5

  25. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Bxc3+ 6.bxc3 c5 7.cxd5 other

  26. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Bxc3+ 6.bxc3 c5 7.e3

  27. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 d5 5.a3 Bxc3+ 6.bxc3 c5 7.other

  28. 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 other


f3-nimzo-indian-package_11042026.zip


The Sicilian Najdorf

  1. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bc4

  2. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bd3

  3. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be2

  4. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e5 7.Nb3 Be6

  5. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e5 7.Nb3 Be7

  6. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e5 7.Nb3 other

  7. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e5 7.other

  8. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e6 7.Be2

  9. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e6 7.f3

  10. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e6 7.other

  11. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 other

  12. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 Nbd7

  13. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 Qb6 8.Qd2 Qxb2 9.Nb3

  14. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 Qb6 8.Qd2 Qxb2 9.Rb1

  15. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 Qb6 8.Qd2 other

  16. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 Qb6 8.other

  17. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 other

  18. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.other

  19. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 other

  20. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Rg1

  21. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.a4

  22. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.f3

  23. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.f4

  24. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.g3

  25. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.h3 e5 7.Nb3

  26. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.h3 e5 7.Nde2

  27. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.h3 e5 7.other

  28. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.h3 e6

  29. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.h3 other

  30. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.other

    Sicilian_Najdorf_11042026.zip


Queen's Gambit Accepted

  1. 1.d4 d5 2.c4 dxc4 3.e4

  2. 1.d4 d5 2.c4 dxc4 3.Nf3

    QGA_11022026.zip


King's Indian Defense

  1. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Bd3

  2. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Be2

  3. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3

  4. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.f3

  5. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.f4

  6. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.h3

  7. 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.other

    KID_package_11042026.zip


Caro-Kann Defense - Finnish variation

  1. 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 h6


Caro-Kann_Finnish_11042026.zip


Halloween Gambit

  1. 1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6 4.Nxe5


Halloween_Gambit_11042026.zip



Benko Gambit

  1. 1.d4 Nf6 2.c4 c5 3.d5 b5 4.cxb5

  2. 1.d4 Nf6 2.c4 c5 3.d5 b5 4.other


Benko_Gambit_package_11042026.zip



Grünfeld Defense

  1. 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.Bf4

  2. 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.Bg5

  3. 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.Nf3

  4. 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5

  5. 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.e3

  6. 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.other

    Grunfeld_Defense_package_11042026.zip


Dragon Sicilian

  1. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Bc4

  2. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be2

  3. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be3 Bg7

  4. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be3 Nc6

  5. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be3 other

  6. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.g3

  7. 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.other


Dragon_package_11042026.zip



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