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Classic game replay

Mario Bertok vs Robert James Fischer, 1962

This replay preserves the complete 62-ply score of Fischer playing Black across 31 numbered moves. The board can be advanced one ply at a time; the notes stick to observable board changes rather than guessing at the players’ intentions.

On this page
  1. Practice positions
  2. Replay with move-by-move board facts
  3. PGN
  4. Sources and checking
  5. Continue with another game
White
Mario Bertok
Black
Robert James Fischer
Event
Stockholm Interzonal
Year
1962
Result
0-1
Opening
D59 Queen's Gambit Declined: Tartakower Defense, Makogonov Exchange Variation

Opening reference: Queen's Gambit Declined: Tartakower Defense, Makogonov Exchange Variation (D59).

In this game, 20 half-moves are labelled opening, 42 middlegame and 0 endgame. The score contains 14 captures and 1 checks or mates; before a recorded move, the position offered a median of 37 legal choices. The source score ends after 31...Bf5 with the recorded result 0-1. Its termination tag was not retained, so this record does not infer whether the game ended by resignation, time or another cause.

Practice positions

The daily trainer uses a short set of positions from this complete score. Each link goes to the exact half-move rather than only the numbered move.

  1. 10...exd5 — Recapture on d510...exd5 was a leading choice in the fixed engine check.
  2. 13...bxc5 — Recapture on c513...bxc5 was a leading choice in the fixed engine check.
  3. 20...Nf6 — Improve the knight20...Nf6 was a leading choice in the fixed engine check.
  4. 28...Be6 — Create pressure on b328...Be6 was a leading choice in the fixed engine check.

Replay with move-by-move board facts

The board, fact panel and transcript use the same legal score. “Fixed engine check” means Stockfish 17.1, one thread, a fixed 25,000-node search and 3 candidate lines. It compares moves under one reproducible setting; it does not claim to reconstruct a player’s thoughts.

♜♞♝♛♚♝♞♜♟♟♟♟♟♟♟♟♟♟♟♟♟♟♟♟♜♞♝♛♚♝♞♜
Mario Bertok vs Robert James Fischer, 1962

Start position

Use Previous and Next on the board, or select a move in the transcript. The board fact and fixed engine check remain visible until you choose another move.

Opening · 1.d4 to 10...exd5

  1. 1.d4 Claim central space

    Board fact: White moves the pawn from d2 to d4; from there it controls e5 and c5.

    Fixed engine check: Near the leading choice · d4 Nf6 Nf3 e6.

  2. 1...d5 Claim central space

    Board fact: Black moves the pawn from d7 to d5; from there it controls e4 and c4.

    Fixed engine check: Ranked first · d5 c4 e6 Nf3.

  3. 2.c4 Change the pawn structure

    Board fact: White moves the pawn from c2 to c4; the move changes the central pawn contact; from c4 it attacks Black's pawn on d5.

    Fixed engine check: Ranked first · c4 e6 Nf3 Nf6.

  4. 2...e6 Advance the e-pawn

    Board fact: Black moves the pawn from e7 to e6; from there it controls d5 and f5.

    Fixed engine check: Ranked first · e6 e3 c5 Nf3.

  5. 3.Nc3 Develop the knight

    Board fact: White develops the knight from b1 to c3; from c3 it attacks Black's pawn on d5.

    Fixed engine check: Ranked first · Nc3 Nf6 Nf3 c5.

  6. 3...Be7 Develop the bishop

    Board fact: Black develops the bishop from f8 to e7; from there it controls c5, d6 and f6.

    Fixed engine check: Ranked first · Be7 Nf3 Nf6 Bf4.

  7. 4.Nf3 Develop the knight

    Board fact: White develops the knight from g1 to f3; from there it controls d4 and e5.

    Fixed engine check: Ranked first · Nf3 Nf6 Bf4 Nbd7.

  8. 4...Nf6 Develop the knight

    Board fact: Black develops the knight from g8 to f6; from there it controls d5 and e4.

    Fixed engine check: Ranked first · Nf6 Bf4.

  9. 5.Bg5 Develop the bishop

    Board fact: White develops the bishop from c1 to g5; from g5 it attacks Black's knight on f6.

    Fixed engine check: Ranked first · Bg5 h6 Bh4 Ne4.

  10. 5...O-O Kingside castling

    Board fact: Black castles kingside, moving the king to g8 and the rook to f8. The move changes king safety and develops the rook in one turn.

    Fixed engine check: Ranked first · O-O e3 Ne4 Bxe7.

  11. 6.e3 Advance the e-pawn

    Board fact: White moves the pawn from e2 to e3; from there it controls d4 and f4.

    Fixed engine check: Ranked first · e3 h6 Bf4 c5.

  12. 6...h6 Create pressure on g5

    Board fact: Black moves the pawn from h7 to h6; from h6 it attacks White's bishop on g5.

    Fixed engine check: Ranked first · h6 Bh4.

  13. 7.Bh4 Create pressure on f6

    Board fact: White moves the bishop from g5 to h4; from h4 it attacks Black's knight on f6.

    Fixed engine check: Ranked first · Bh4 c5 dxc5 dxc4.

  14. 7...b6 Advance the b-pawn

    Board fact: Black moves the pawn from b7 to b6; from there it controls c5.

    Fixed engine check: Ranked first · b6 cxd5 Nxd5 Nxd5.

  15. 8.cxd5 Exchange on d5

    Board fact: White's pawn takes the pawn on d5; the move changes the central pawn contact; White accepts doubled pawns on the d-file; from d5 it attacks Black's pawn on e6; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · cxd5 Nxd5.

  16. 8...Nxd5 Recapture on d5

    Board fact: Black's knight recaptures the pawn on d5; from d5 it attacks White's knight on c3 and White's pawn on e3; material is level after the capture.

    Fixed engine check: Ranked first · Nxd5 Nxd5 exd5 Bxe7.

  17. 9.Bxe7 Exchange on e7

    Board fact: White's bishop takes the bishop on e7; from e7 it attacks Black's queen on d8 and Black's rook on f8; white is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxe7 Qxe7 Nxd5 exd5.

  18. 9...Qxe7 Recapture on e7

    Board fact: Black's queen recaptures the bishop on e7; from e7 it reinforces the rook on f8; material is level after the capture.

    Fixed engine check: Ranked first · Qxe7 Nxd5 exd5 Rc1.

  19. 10.Nxd5 Exchange on d5

    Board fact: White's knight takes the knight on d5; from d5 it attacks Black's queen on e7 and Black's pawn on b6; white is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Nxd5 exd5 Rc1 Bb7.

  20. 10...exd5 Recapture on d5

    Board fact: Black's pawn recaptures the knight on d5; the move changes the central pawn contact; material is level after the capture.

    Fixed engine check: Ranked first · exd5 Rc1 Bb7 Bd3.

Middlegame · 11.Be2 to 31...Bf5

  1. 11.Be2 Develop the bishop

    Board fact: White develops the bishop from f1 to e2; from there it controls c4, d3 and f3.

    Fixed engine check: Ranked first · Be2 Rd8 Rc1 Bf5.

  2. 11...Be6 Develop the bishop

    Board fact: Black develops the bishop from c8 to e6; from there it controls d5 and f5.

    Fixed engine check: Ranked first · Be6 Rc1 c5 dxc5.

  3. 12.O-O Kingside castling

    Board fact: White castles kingside, moving the king to g1 and the rook to f1. The move changes king safety and develops the rook in one turn.

    Fixed engine check: Ranked first · O-O c5.

  4. 12...c5 Change the pawn structure

    Board fact: Black moves the pawn from c7 to c5; the move changes the central pawn contact; from c5 it attacks White's pawn on d4.

    Fixed engine check: Ranked first · c5 b3 Nd7 Rc1.

  5. 13.dxc5 Exchange on c5

    Board fact: White's pawn takes the pawn on c5; the move changes the central pawn contact; from c5 it attacks Black's pawn on b6; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · dxc5 bxc5 Ne5 Nd7.

  6. 13...bxc5 Recapture on c5

    Board fact: Black's pawn recaptures the pawn on c5; the move changes the central pawn contact; material is level after the capture.

    Fixed engine check: Ranked first · bxc5 Ne5 Nd7 Nd3.

  7. 14.Qa4 Create pressure on a7

    Board fact: White moves the queen from d1 to a4; from a4 it attacks Black's pawn on a7.

    Fixed engine check: Ranked first · Qa4 Nd7 Qa3 Qd6.

  8. 14...Qb7 Create pressure on b2

    Board fact: Black moves the queen from e7 to b7; from b7 it attacks White's pawn on b2.

    Fixed engine check: Near the leading choice · Qb7 b3.

  9. 15.Qa3 Create pressure on a7

    Board fact: White moves the queen from a4 to a3; from a3 it attacks Black's pawn on a7 and Black's pawn on c5.

    Fixed engine check: Near the leading choice · Qa3 Nd7.

  10. 15...Nd7 Develop the knight

    Board fact: Black develops the knight from b8 to d7; from there it controls e5, c5 and f6.

    Fixed engine check: Ranked first · Nd7 b3 a5 Ne1.

  11. 16.Ne1 Reroute the knight

    Board fact: White moves the knight from f3 to e1; from there it controls d3 and f3.

    Fixed engine check: Ranked first · Ne1.

  12. 16...a5 Advance the a-pawn

    Board fact: Black moves the pawn from a7 to a5.

    Fixed engine check: Ranked first · a5 b3 a4 bxa4.

  13. 17.Nd3 Develop the knight

    Board fact: White develops the knight from e1 to d3; from d3 it attacks Black's pawn on c5.

    Fixed engine check: Ranked first · Nd3 c4 Nf4 Qb4.

  14. 17...c4 Create pressure on d3

    Board fact: Black moves the pawn from c5 to c4; from c4 it attacks White's knight on d3.

    Fixed engine check: Ranked first · c4 Nf4 Qb4 Rfd1.

  15. 18.Nf4 Create pressure on e6

    Board fact: White moves the knight from d3 to f4; from f4 it attacks Black's bishop on e6 and Black's pawn on d5.

    Fixed engine check: Ranked first · Nf4 Qb4 Qxb4 axb4.

  16. 18...Rfb8 Rook on the semi-open b-file

    Board fact: Black moves the rook from f8 to b8; the rook now works on a semi-open b-file; from b8 it reinforces the queen on b7.

    Fixed engine check: Ranked first · Rfb8 Nxe6 fxe6 b3.

  17. 19.Rab1 Improve the rook

    Board fact: White moves the rook from a1 to b1; from b1 it reinforces the rook on f1.

    Fixed engine check: Near the leading choice · Rab1 Nf6 Nxe6 fxe6.

  18. 19...Bf5 Create pressure on b1

    Board fact: Black moves the bishop from e6 to f5; from f5 it attacks White's rook on b1.

    Fixed engine check: Ranked first · Bf5 Rbd1 Nf6 Rd2.

  19. 20.Rbd1 Rook on the semi-open d-file

    Board fact: White moves the rook from b1 to d1; the rook now works on a semi-open d-file; from d1 it attacks Black's pawn on d5.

    Fixed engine check: Ranked first · Rbd1 Nf6 Rd2 g5.

  20. 20...Nf6 Improve the knight

    Board fact: Black moves the knight from d7 to f6; from there it controls d5 and e4.

    Fixed engine check: Ranked first · Nf6 Bf3 Qxb2 Qxb2.

  21. 21.Rd2 Rook on the semi-open d-file

    Board fact: White moves the rook from d1 to d2; the rook now works on a semi-open d-file; from d2 it attacks Black's pawn on d5.

    Fixed engine check: Ranked first · Rd2 g5 Nxd5 Nxd5.

  22. 21...g5 Create pressure on f4

    Board fact: Black moves the pawn from g7 to g5; from g5 it attacks White's knight on f4.

    Fixed engine check: Ranked first · g5 Nxd5 Nxd5 Bf3.

  23. 22.Nxd5 Exchange on d5

    Board fact: White's knight takes the pawn on d5; from d5 it attacks Black's knight on f6; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Nxd5 Nxd5 Bf3 Bd3.

  24. 22...Nxd5 Recapture on d5

    Board fact: Black's knight recaptures the knight on d5; from d5 it attacks White's pawn on e3; black is ahead by 2 conventional material points after the capture.

    Fixed engine check: Ranked first · Nxd5 Bf3 Bd3 Rfd1.

  25. 23.Bxc4 Exchange on c4

    Board fact: White's bishop takes the pawn on c4; from c4 it attacks Black's knight on d5; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Playable; Bf3 ranked higher · Bxc4 Be6 Rfd1 Nc7.

  26. 23...Be6 Reposition the bishop

    Board fact: Black moves the bishop from f5 to e6; from there it controls d5 and f5.

    Fixed engine check: Ranked first · Be6 Rfd1 Nc7 Be2.

  27. 24.Rfd1 Rook on the open d-file

    Board fact: White moves the rook from f1 to d1; the rook now occupies the open d-file; from d1 it reinforces the rook on d2.

    Fixed engine check: Near the leading choice · Rfd1 Nxe3.

  28. 24...Nxe3 Exchange on e3

    Board fact: Black's knight takes the pawn on e3; from e3 it attacks White's rook on d1 and White's bishop on c4; black is ahead by 2 conventional material points after the capture.

    Fixed engine check: Ranked first · Nxe3 Qxe3 Bxc4 h4.

  29. 25.Qxe3 Recapture on e3

    Board fact: White's queen recaptures the knight on e3; from e3 it attacks Black's bishop on e6 and Black's pawn on g5; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Qxe3 Bxc4 Qd4 Be6.

  30. 25...Bxc4 Exchange on c4

    Board fact: Black's bishop takes the bishop on c4; from c4 it attacks White's pawn on a2; black is ahead by 2 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxc4 Qh3 Qe7 b3.

  31. 26.h4 Create pressure on g5

    Board fact: White moves the pawn from h2 to h4; from h4 it attacks Black's pawn on g5.

    Fixed engine check: Ranked first · h4 Re8 Qg3 Qe7.

  32. 26...Re8 Rook on the open e-file

    Board fact: Black moves the rook from b8 to e8; the rook now occupies the open e-file; from e8 it attacks White's queen on e3.

    Fixed engine check: Ranked first · Re8 Qc5 Qb4 Qf5.

  33. 27.Qg3 Create pressure on g5

    Board fact: White moves the queen from e3 to g3; from g3 it attacks Black's pawn on g5.

    Fixed engine check: Ranked first · Qg3 Qe7 b3 Be6.

  34. 27...Qe7 Reposition the queen

    Board fact: Black moves the queen from b7 to e7; from there it controls e4, e5 and c5.

    Fixed engine check: Ranked first · Qe7 b3 Be6 Re2.

  35. 28.b3 Create pressure on c4

    Board fact: White moves the pawn from b2 to b3; from b3 it attacks Black's bishop on c4.

    Fixed engine check: Ranked first · b3 Be6 Re1 Qf6.

  36. 28...Be6 Create pressure on b3

    Board fact: Black moves the bishop from c4 to e6; from e6 it attacks White's pawn on b3.

    Fixed engine check: Ranked first · Be6 f4 g4 Re1.

  37. 29.f4 Change the pawn structure

    Board fact: White moves the pawn from f2 to f4; the move changes the central pawn contact; from f4 it attacks Black's pawn on g5.

    Fixed engine check: Playable; Re1 ranked higher · f4 g4 f5 Qc5+.

  38. 29...g4 Advance the g-pawn

    Board fact: Black moves the pawn from g5 to g4; from there it controls f3.

    Fixed engine check: Ranked first · g4 Re1 Qc5+ Rf2.

  39. 30.h5 Advance the h-pawn

    Board fact: White moves the pawn from h4 to h5.

    Fixed engine check: Recorded move; Rc1 ranked higher · h5 Rad8 Kh2 Rxd2.

  40. 30...Qc5+ A forcing check

    Board fact: Black moves the queen from e7 to c5; the move checks White's king; from c5 it attacks White's pawn on h5.

    Fixed engine check: Ranked first · Qc5+ Kh2 Qxh5+ Kg1.

  41. 31.Rf2 Answering the check

    Board fact: White answers the check by moving the rook from d2 to f2; from there it controls f3 and f4.

    Fixed engine check: Playable; Qf2 ranked higher · Rf2 Rad8 Rxd8 Rxd8.

  42. 31...Bf5 Reposition the bishop

    Board fact: Black moves the bishop from e6 to f5; from there it controls e4, d3 and e6.

    Fixed engine check: Ranked first · Bf5 Kh2 Rad8 Rxd8.

PGN

[Event "Stockholm Interzonal"] [Site "?"] [Date "1962.??.??"] [White "Bertok, Mario"] [Black "Fischer, Robert James"] [Result "0-1"] 1. d4 d5 2. c4 e6 3. Nc3 Be7 4. Nf3 Nf6 5. Bg5 O-O 6. e3 h6 7. Bh4 b6 8. cxd5 Nxd5 9. Bxe7 Qxe7 10. Nxd5 exd5 11. Be2 Be6 12. O-O c5 13. dxc5 bxc5 14. Qa4 Qb7 15. Qa3 Nd7 16. Ne1 a5 17. Nd3 c4 18. Nf4 Rfb8 19. Rab1 Bf5 20. Rbd1 Nf6 21. Rd2 g5 22. Nxd5 Nxd5 23. Bxc4 Be6 24. Rfd1 Nxe3 25. Qxe3 Bxc4 26. h4 Re8 27. Qg3 Qe7 28. b3 Be6 29. f4 g4 30. h5 Qc5+ 31. Rf2 Bf5 0-1

Sources and checking

Score source: Chess Database, version 1 by Ana Schaigorodsky (2016), licensed under CC BY 4.0. LibreChess selected the exact score identified by sha256:689bb60efc9dc18f9abe85002473c4360f222379b0493b13ec8e9fa7f2725f45 and pins it in the selection manifest.
Exact Figshare tags:
White="Bertok, Mario"; Black="Fischer, Robert James"; Event="Stockholm Interzonal"; Date="1962.03.04"; Result="0-1". LibreChess parsed the main line with chess.js and stores normalised SAN. Source comments, side variations and termination detail were not retained.

LibreChess checks every SAN move with chess.js and compares the result and move sequence with a stored reference. The engine comparison was calculated offline from the fixed settings above; it is not a source for historical claims. No termination is inferred where the imported score does not preserve one.

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