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Fischer's Najdorf Counterstrike

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Robert Byrne advances his f-pawn early against Bobby Fischer's Najdorf. Fischer replies on the same wing, then uses checks and threats to keep White's king and pieces awkwardly placed.

On this page
  1. Critical decisions
  2. Replay with move-by-move board facts
  3. PGN
  4. Sources and checking
  5. Continue with another game
White
Robert E Byrne
Black
Robert James Fischer
Event
Sousse Interzonal+
Year
1967
Result
0-1
Opening
B87 Sicilian Defense: Sozin Attack, Flank Variation

Opening reference: Sicilian Defense: Sozin Attack, Flank Variation (B87).

In this game, 20 half-moves are labelled opening, 36 middlegame and 0 endgame. The score contains 13 captures and 3 checks or mates; before a recorded move, the position offered a median of 36 legal choices. The source score ends after 28...Qf4 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.

Critical decisions

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. 9...e5 — Change the pawn structure9...e5 was a leading choice in the fixed engine check.
  2. 16...Bxh4 — Move 16 — ...Bxh4, an active bishop16...Bxh4 was a leading choice in the fixed engine check.
  3. 21...Bh2+ — Moves 20-22 — the bishop infiltrates21...Bh2+ was a leading choice in the fixed engine check.
  4. 27...Qxf6+ — Moves 27-28 — the queen enters on f427...Qxf6+ 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.

♜♞♝♛♚♝♞♜♟♟♟♟♟♟♟♟♟♟♟♟♟♟♟♟♜♞♝♛♚♝♞♜
Robert E Byrne vs Robert James Fischer, 1967

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.e4 to 10...Nbd7

  1. 1.e4 Claim central space

    Board fact: White moves the pawn from e2 to e4; from there it controls d5 and f5.

    Fixed engine check: Ranked first · e4 e5 Nf3 Nc6.

  2. 1...c5 Advance the c-pawn

    Board fact: Black moves the pawn from c7 to c5; from there it controls d4.

    Fixed engine check: Ranked first · c5 Nc3 Nc6 Nf3.

  3. 2.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 e6 c3 d5.

  4. 2...d6 Advance the d-pawn

    Board fact: Black moves the pawn from d7 to d6; from there it controls e5 and c5.

    Fixed engine check: Ranked first · d6 Nc3 a6 d4.

  5. 3.d4 Change the pawn structure

    Board fact: White moves the pawn from d2 to d4; the move changes the central pawn contact; from d4 it attacks Black's pawn on c5.

    Fixed engine check: Ranked first · d4 cxd4 Nxd4 Nf6.

  6. 3...cxd4 Exchange on d4

    Board fact: Black's pawn takes the pawn on d4; the move changes the central pawn contact; Black accepts doubled pawns on the d-file; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · cxd4 Nxd4.

  7. 4.Nxd4 Recapture on d4

    Board fact: White's knight recaptures the pawn on d4; from d4 it reinforces the pawn on c2; material is level after the capture.

    Fixed engine check: Ranked first · Nxd4 Nf6 Nc3 a6.

  8. 4...Nf6 Develop the knight

    Board fact: Black develops the knight from g8 to f6; from f6 it attacks White's pawn on e4.

    Fixed engine check: Ranked first · Nf6 Nc3.

  9. 5.Nc3 Develop the knight

    Board fact: White develops the knight from b1 to c3; from there it controls d5 and e4.

    Fixed engine check: Ranked first · Nc3 g6 Be3 Nc6.

  10. 5...a6 Advance the a-pawn

    Board fact: Black moves the pawn from a7 to a6.

    Fixed engine check: Ranked first · a6 Bg5 Nbd7 Be2.

  11. 6.Bc4 Develop the bishop

    Board fact: White develops the bishop from f1 to c4; from c4 it attacks Black's pawn on a6 and Black's pawn on f7.

    Fixed engine check: Ranked first · Bc4 e6 Bb3 b5.

  12. 6...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 f4.

  13. 7.Bb3 Create pressure on e6

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

    Fixed engine check: Ranked first · Bb3 Be7 g4 h6.

  14. 7...b5 Advance the b-pawn

    Board fact: Black moves the pawn from b7 to b5; from there it controls c4.

    Fixed engine check: Ranked first · b5 Be3 Qc7 f4.

  15. 8.f4 Advance the f-pawn

    Board fact: White moves the pawn from f2 to f4; from there it controls e5.

    Fixed engine check: Near the leading choice · f4 Bb7.

  16. 8...Bb7 Develop the bishop

    Board fact: Black develops the bishop from c8 to b7; from b7 it attacks White's pawn on e4.

    Fixed engine check: Near the leading choice · Bb7 e5 dxe5 fxe5.

  17. 9.f5 Change the pawn structure

    Board fact: White moves the pawn from f4 to f5; the move changes the central pawn contact; from f5 it attacks Black's pawn on e6.

    Fixed engine check: Playable; e5 ranked higher · f5 e5.

  18. 9...e5 Change the pawn structure

    Board fact: Black moves the pawn from e6 to e5; the move changes the central pawn contact; from e5 it attacks White's knight on d4.

    Fixed engine check: Ranked first · e5 Nde2.

  19. 10.Nde2 Reroute the knight

    Board fact: White moves the knight from d4 to e2; from there it controls d4, c3 and f4.

    Fixed engine check: Ranked first · Nde2 Nbd7 Be3 Be7.

  20. 10...Nbd7 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 · Nbd7 Be3.

Middlegame · 11.Bg5 to 28...Qf4

  1. 11.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 Be7.

  2. 11...Be7 Develop the bishop

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

    Fixed engine check: Ranked first · Be7 a3 h5 Qd2.

  3. 12.Ng3 Reroute the knight

    Board fact: White moves the knight from e2 to g3; from there it controls e4 and f5.

    Fixed engine check: Ranked first · Ng3 O-O O-O Rc8.

  4. 12...Rc8 Rook on the semi-open c-file

    Board fact: Black moves the rook from a8 to c8; the rook now works on a semi-open c-file; from c8 it attacks White's knight on c3.

    Fixed engine check: Near the leading choice · Rc8 Nh5 Nxh5 Qxh5.

  5. 13.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: Playable; Bxf6 ranked higher · O-O h5.

    Move 13 — ...h5!, meeting flank with flank13...h5 stops White's h-pawn from advancing freely and gives Black control of g4. White nevertheless continues with 14.h4, and Black counters on the queenside with ...b4.
  6. 13...h5 Advance the h-pawn

    Board fact: Black moves the pawn from h7 to h5.

    Fixed engine check: Ranked first · h5 Bh4 b4 Na4.

  7. 14.h4 Advance the h-pawn

    Board fact: White moves the pawn from h2 to h4; from h4 it reinforces the bishop on g5.

    Fixed engine check: Near the leading choice · h4 b4.

  8. 14...b4 Create pressure on c3

    Board fact: Black moves the pawn from b5 to b4; from b4 it attacks White's knight on c3.

    Fixed engine check: Ranked first · b4 Na4 Nxe4 Nxe4.

  9. 15.Bxf6 Exchange on f6

    Board fact: White's bishop takes the knight on f6; from f6 it attacks Black's bishop on e7 and Black's pawn on e5; white is ahead by 3 conventional material points after the capture.

    Fixed engine check: Near the leading choice · Bxf6 Nxf6 Nd5 Bxd5.

  10. 15...Bxf6 Recapture on f6

    Board fact: Black's bishop recaptures the bishop on f6; from f6 it attacks White's pawn on h4; material is level after the capture.

    Fixed engine check: Ranked first · Bxf6 Na4 Bxh4 f6.

  11. 16.Nd5 Create pressure on f6

    Board fact: White moves the knight from c3 to d5; from d5 it attacks Black's bishop on f6 and Black's pawn on b4.

    Fixed engine check: Playable; Na4 ranked higher · Nd5 Bxh4 Rf3 Nc5.

    Move 16 — ...Bxh4, an active bishop16...Bxh4 takes a pawn; it is not a sacrifice. White's 17.Nxh5 captures the pawn on h5, not the bishop on h4, which later enters through g3 and h2.
  12. 16...Bxh4 Exchange on h4

    Board fact: Black's bishop takes the pawn on h4; from h4 it attacks White's knight on g3; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Bxh4 Rf3 Kf8 a3.

  13. 17.Nxh5 Exchange on h5

    Board fact: White's knight takes the pawn on h5; from h5 it attacks Black's pawn on g7; material is level after the capture.

    Fixed engine check: Recorded move; Rf3 ranked higher · Nxh5 Qg5 f6 g6.

  14. 17...Qg5 Create pressure on h5

    Board fact: Black moves the queen from d8 to g5; from g5 it attacks White's knight on h5 and White's pawn on f5.

    Fixed engine check: Ranked first · Qg5 f6 g6 Ng7+.

  15. 18.f6 Change the pawn structure

    Board fact: White moves the pawn from f5 to f6; the move changes the central pawn contact; from f6 it attacks Black's pawn on g7.

    Fixed engine check: Ranked first · f6 g6 Ng7+ Kd8.

  16. 18...g6 Create pressure on h5

    Board fact: Black moves the pawn from g7 to g6; from g6 it attacks White's knight on h5.

    Fixed engine check: Ranked first · g6 Ng7+ Kd8 Rf3.

  17. 19.Ng7+ A forcing check

    Board fact: White moves the knight from h5 to g7; the move checks Black's king; from there it controls e6 and f5.

    Fixed engine check: Ranked first · Ng7+ Kd8.

  18. 19...Kd8 Answering the check

    Board fact: Black answers the check by moving the king from e8 to d8; from d8 it reinforces the rook on c8.

    Fixed engine check: Near the leading choice · Kd8 Rf3.

  19. 20.Rf3 Improve the rook

    Board fact: White moves the rook from f1 to f3; from there it controls c3, d3 and e3.

    Fixed engine check: Ranked first · Rf3 Nc5 Nf4 Kc7.

    Moves 20-22 — the bishop infiltratesThe same bishop reaches g3 with 20...Bg3, then checks from h2 after 21.Qd3. White's king goes to f1 while the knight on g7 has no quick route back to the centre.
  20. 20...Bg3 Reposition the bishop

    Board fact: Black moves the bishop from h4 to g3; from there it controls e5 and f4.

    Fixed engine check: Ranked first · Bg3 Qd3 Qh4 Rxg3.

  21. 21.Qd3 Create pressure on a6

    Board fact: White moves the queen from d1 to d3; from d3 it attacks Black's pawn on a6.

    Fixed engine check: Ranked first · Qd3 Qh4 Rxg3 Qh1+.

  22. 21...Bh2+ A forcing check

    Board fact: Black moves the bishop from g3 to h2; the move checks White's king; from there it controls e5 and f4.

    Fixed engine check: Ranked first · Bh2+ Kf1 Nc5 Rh3.

  23. 22.Kf1 Answering the check

    Board fact: White answers the check by moving the king from g1 to f1; from f1 it reinforces the pawn on g2.

    Fixed engine check: Ranked first · Kf1 Bf4 Rh3 Rxh3.

  24. 22...Nc5 Create pressure on d3

    Board fact: Black moves the knight from d7 to c5; from c5 it attacks White's queen on d3 and White's bishop on b3.

    Fixed engine check: Ranked first · Nc5 Rh3 Rh4 Qf3.

  25. 23.Rh3 Rook on the open h-file

    Board fact: White moves the rook from f3 to h3; the rook now occupies the open h-file; from h3 it attacks Black's rook on h8 and Black's bishop on h2.

    Fixed engine check: Ranked first · Rh3 Rh4 Qf3 Nxe4.

  26. 23...Rh4 Rook on the open h-file

    Board fact: Black moves the rook from h8 to h4; the rook now occupies the open h-file; from h4 it attacks White's rook on h3 and White's pawn on e4.

    Fixed engine check: Ranked first · Rh4 Rxh4 Qxh4 Qh3.

  27. 24.Qf3 Reposition the queen

    Board fact: White moves the queen from d3 to f3; from there it controls e4, c3 and d3.

    Fixed engine check: Ranked first · Qf3 Nxb3.

  28. 24...Nxb3 Exchange on b3

    Board fact: Black's knight takes the bishop on b3; from b3 it attacks White's rook on a1; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Nxb3 axb3 Rxh3 Qxh3.

  29. 25.axb3 Recapture on b3

    Board fact: White's pawn recaptures the knight on b3; the move changes the central pawn contact; White accepts doubled pawns on the b-file; material is level after the capture.

    Fixed engine check: Ranked first · axb3 Bxd5.

  30. 25...Rxh3 Exchange on h3

    Board fact: Black's rook takes the rook on h3; the rook now occupies the open h-file; from h3 it attacks White's queen on f3; black is ahead by 5 conventional material points after the capture.

    Fixed engine check: Ranked first · Rxh3 Qxh3 Bxd5 exd5.

  31. 26.Qxh3 Recapture on h3

    Board fact: White's queen recaptures the rook on h3; from h3 it attacks Black's rook on c8 and Black's bishop on h2; material is level after the capture.

    Fixed engine check: Near the leading choice · Qxh3 Bxd5 exd5 Qxf6+.

  32. 26...Bxd5 Exchange on d5

    Board fact: Black's bishop takes the knight on d5; from d5 it attacks White's pawn on b3 and White's pawn on e4; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxd5 exd5 Qxf6+ Qf3.

  33. 27.exd5 Recapture on d5

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

    Fixed engine check: Ranked first · exd5 Qxf6+ Qf3 Qxf3+.

    Moves 27-28 — the queen enters on f4After 26...Bxd5 27.exd5 Qxf6+ 28.Ke1 Qf4, Black's queen has entered with tempo, supports the bishop on h2 and eyes f2 and c1. The stored score ends in this position.
  34. 27...Qxf6+ Capture with check on f6

    Board fact: Black's queen takes the pawn on f6; the move checks White's king; from f6 it attacks White's knight on g7; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Qxf6+ Qf3 Qxg7 Rxa6.

  35. 28.Ke1 Answering the check

    Board fact: White answers the check by moving the king from f1 to e1.

    Fixed engine check: Ranked first · Ke1 Qf4 Qf3 Bg3+.

  36. 28...Qf4 Reposition the queen

    Board fact: Black moves the queen from f6 to f4; from there it controls d4, e4 and e5.

    Fixed engine check: Ranked first · Qf4 Ne6+ fxe6 c4.

PGN

[Event "Sousse Interzonal+"] [Site "?"] [Date "1967.??.??"] [White "Byrne, Robert E"] [Black "Fischer, Robert James"] [Result "0-1"] 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Bc4 e6 7. Bb3 b5 8. f4 Bb7 9. f5 e5 10. Nde2 Nbd7 11. Bg5 Be7 12. Ng3 Rc8 13. O-O h5 14. h4 b4 15. Bxf6 Bxf6 16. Nd5 Bxh4 17. Nxh5 Qg5 18. f6 g6 19. Ng7+ Kd8 20. Rf3 Bg3 21. Qd3 Bh2+ 22. Kf1 Nc5 23. Rh3 Rh4 24. Qf3 Nxb3 25. axb3 Rxh3 26. Qxh3 Bxd5 27. exd5 Qxf6+ 28. Ke1 Qf4 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 sha256:9eb01e65dddb7f5e6202481b5b021dcf24d48bc77c7683df6df667f06495a188 and pins it in the selection manifest.
Exact Figshare tags:
White="Byrne, Robert E"; Black="Fischer, Robert James"; Event="Sousse Interzonal+"; Date="1967.??.??"; 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 or a substitute for the authored notes. No termination is inferred where the imported score does not preserve one.

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