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Classic game replay

Adolf Anderssen vs Jozsef Szen, 1851

This replay preserves the complete 83-ply score of Anderssen playing White across 42 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
Adolf Anderssen
Black
Jozsef Szen
Event
London
Year
1851
Result
1-0
Opening
C01 French Defense: Exchange Variation, Monte Carlo Variation

Opening reference: French Defense: Exchange Variation, Monte Carlo Variation (C01).

In this game, 20 half-moves are labelled opening, 63 middlegame and 0 endgame. The score contains 16 captures and 6 checks or mates; before a recorded move, the position offered a median of 37 legal choices. The source score ends after 42.Re5 with the recorded result 1-0. 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. 9.Bxc4 — Recapture on c49.Bxc4 was a leading choice in the fixed engine check.
  2. 12.O-O — Kingside castling12.O-O was a leading choice in the fixed engine check.
  3. 23.d5 — Advance a passed pawn23.d5 was a leading choice in the fixed engine check.
  4. 26.d6+ — A forcing check26.d6+ was a leading choice in the fixed engine check.
  5. 37.Qd3+ — A forcing check37.Qd3+ 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.

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Adolf Anderssen vs Jozsef Szen, 1851

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...c6

  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...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 d4.

  3. 2.d4 Claim central space

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

    Fixed engine check: Ranked first · d4 d5 e5 c5.

  4. 2...d5 Change the pawn structure

    Board fact: Black moves the pawn from d7 to d5; the move changes the central pawn contact; from d5 it attacks White's pawn on e4.

    Fixed engine check: Ranked first · d5 e5 c5 c3.

  5. 3.exd5 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 · exd5 exd5 Nf3 Nf6.

  6. 3...exd5 Recapture on d5

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

    Fixed engine check: Ranked first · exd5 Nf3 Nf6 Bd3.

  7. 4.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: Near the leading choice · c4 Bb4+ Nc3 Qe7+.

  8. 4...Bb4+ A forcing check

    Board fact: Black develops the bishop from f8 to b4; the move checks White's king; from there it controls c3, c5 and d6.

    Fixed engine check: Ranked first · Bb4+.

  9. 5.Nc3 Answering the check

    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 O-O.

  10. 5...Qe7+ A forcing check

    Board fact: Black moves the queen from d8 to e7; the move checks White's king; from there it controls e4, e5 and c5.

    Fixed engine check: Near the leading choice · Qe7+ Be2.

  11. 6.Be3 Answering the check

    Board fact: White develops the bishop from c1 to e3; from there it controls d4 and f4.

    Fixed engine check: Near the leading choice · Be3 Nf6.

  12. 6...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 Nf3 Nbd7 Bd3.

  13. 7.h3 Advance the h-pawn

    Board fact: White moves the pawn from h2 to h3.

    Fixed engine check: Ranked first · h3.

  14. 7...Be6 Develop the bishop

    Board fact: Black develops the bishop from c8 to e6; from e6 it attacks White's pawn on h3.

    Fixed engine check: Near the leading choice · Be6 c5.

  15. 8.Qb3 Create pressure on b4

    Board fact: White moves the queen from d1 to b3; from b3 it attacks Black's bishop on b4.

    Fixed engine check: Playable; c5 ranked higher · Qb3 Nc6 c5 O-O.

  16. 8...dxc4 Exchange on c4

    Board fact: Black's pawn takes the pawn on c4; the move changes the central pawn contact; Black accepts doubled pawns on the c-file; from c4 it attacks White's queen on b3; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Playable; Nc6 ranked higher · dxc4 Bxc4.

  17. 9.Bxc4 Recapture on c4

    Board fact: White's bishop recaptures the pawn on c4; from c4 it attacks Black's bishop on e6; material is level after the capture.

    Fixed engine check: Ranked first · Bxc4 Nc6 Nf3 Na5.

  18. 9...Bxc4 Recapture on c4

    Board fact: Black's bishop recaptures the bishop on c4; from c4 it attacks White's queen on b3; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxc4 Qxc4 Nc6 Nf3.

  19. 10.Qxc4 Recapture on c4

    Board fact: White's queen recaptures the bishop on c4; from c4 it attacks Black's bishop on b4 and Black's pawn on c7; material is level after the capture.

    Fixed engine check: Ranked first · Qxc4 Nc6.

  20. 10...c6 Advance the c-pawn

    Board fact: Black moves the pawn from c7 to c6; from there it controls d5.

    Fixed engine check: Near the leading choice · c6 Nf3 Na6 O-O.

Middlegame · 11.Nf3 to 42.Re5

  1. 11.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 Na6.

  2. 11...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.

  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 O-O Qb3 Rfe8.

  4. 12...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 Qb3 Rfe8 d5.

  5. 13.Rae1 Rook on the open e-file

    Board fact: White moves the rook from a1 to e1; the rook now occupies the open e-file; from there it controls e3.

    Fixed engine check: Near the leading choice · Rae1.

  6. 13...Qe6 Create pressure on c4

    Board fact: Black moves the queen from e7 to e6; from e6 it attacks White's queen on c4 and White's bishop on e3.

    Fixed engine check: Recorded move; Ba5 ranked higher · Qe6 Qxb4 a5 Qb3.

  7. 14.Ne5 Create pressure on d7

    Board fact: White moves the knight from f3 to e5; from e5 it attacks Black's knight on d7 and Black's pawn on c6.

    Fixed engine check: Recorded move; Qxb4 ranked higher · Ne5 Nxe5.

  8. 14...Bxc3 Exchange on c3

    Board fact: Black's bishop takes the knight on c3; from c3 it attacks White's rook on e1 and White's pawn on b2; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Playable; Nxe5 ranked higher · Bxc3 Qxe6 fxe6 bxc3.

  9. 15.bxc3 Recapture on c3

    Board fact: White's pawn recaptures the bishop on c3; the move changes the central pawn contact; from c3 it reinforces the pawn on d4; material is level after the capture.

    Fixed engine check: Near the leading choice · bxc3 Nxe5 Qxe6 Nf3+.

  10. 15...Nd5 Create pressure on e3

    Board fact: Black moves the knight from f6 to d5; from d5 it attacks White's bishop on e3 and White's pawn on c3.

    Fixed engine check: Playable; Nxe5 ranked higher · Nd5 Bd2.

  11. 16.Bc1 Reposition the bishop

    Board fact: White moves the bishop from e3 to c1; from there it controls e3 and f4.

    Fixed engine check: Ranked first · Bc1 b5.

  12. 16...Rfe8 Rook on the open e-file

    Board fact: Black moves the rook from f8 to e8; the rook now occupies the open e-file; from there it controls e6.

    Fixed engine check: Ranked first · Rfe8 Qb3.

  13. 17.Nxd7 Exchange on d7

    Board fact: White's knight takes the knight on d7; white is ahead by 3 conventional material points after the capture.

    Fixed engine check: Near the leading choice · Nxd7.

  14. 17...Qxd7 Recapture on d7

    Board fact: Black's queen recaptures the knight on d7; from d7 it attacks White's pawn on h3; material is level after the capture.

    Fixed engine check: Ranked first · Qxd7 Qb3.

  15. 18.Qb3 Create pressure on d5

    Board fact: White moves the queen from c4 to b3; from b3 it attacks Black's knight on d5 and Black's pawn on b7.

    Fixed engine check: Ranked first · Qb3 b5 c4 Nb6.

  16. 18...h6 Advance the h-pawn

    Board fact: Black moves the pawn from h7 to h6.

    Fixed engine check: Near the leading choice · h6 Rxe8+ Rxe8 c4.

  17. 19.c4 Create pressure on d5

    Board fact: White moves the pawn from c3 to c4; from c4 it attacks Black's knight on d5.

    Fixed engine check: Ranked first · c4 Rxe1 Rxe1 Nf6.

  18. 19...Nf6 Improve the knight

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

    Fixed engine check: Ranked first · Nf6 Rxe8+.

  19. 20.Rd1 Improve the rook

    Board fact: White moves the rook from e1 to d1; from there it controls d4 and d3.

    Fixed engine check: Near the leading choice · Rd1 Rad8.

  20. 20...Rad8 Rook on the semi-open d-file

    Board fact: Black moves the rook from a8 to d8; the rook now works on a semi-open d-file; from d8 it reinforces the queen on d7.

    Fixed engine check: Ranked first · Rad8 Rd3 Qc7 Be3.

  21. 21.Bb2 Develop the bishop

    Board fact: White develops the bishop from c1 to b2; from there it controls d4 and c3.

    Fixed engine check: Near the leading choice · Bb2 Qf5 d5 cxd5.

  22. 21...b5 Create pressure on c4

    Board fact: Black moves the pawn from b7 to b5; from b5 it attacks White's pawn on c4.

    Fixed engine check: Ranked first · b5 cxb5 Rb8 bxc6.

  23. 22.cxb5 Exchange on b5

    Board fact: White's pawn takes the pawn on b5; the move changes the central pawn contact; from b5 it attacks Black's pawn on c6; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · cxb5 Rb8 bxc6 Qxc6.

  24. 22...cxb5 Recapture on b5

    Board fact: Black's pawn recaptures the pawn on b5; the move changes the central pawn contact; material is level after the capture.

    Fixed engine check: Ranked first · cxb5 d5.

  25. 23.d5 Advance a passed pawn

    Board fact: White moves the pawn from d4 to d5; the pawn is now passed; from there it controls c6 and e6.

    Fixed engine check: Ranked first · d5 Ne4 Qb4 Rc8.

  26. 23...Ne4 Create pressure on f2

    Board fact: Black moves the knight from f6 to e4; from e4 it attacks White's pawn on f2.

    Fixed engine check: Ranked first · Ne4 Rd4 Nf6 Qf3.

  27. 24.Rd4 Create pressure on e4

    Board fact: White moves the rook from d1 to d4; from d4 it attacks Black's knight on e4.

    Fixed engine check: Ranked first · Rd4 a6.

  28. 24...f6 Advance the f-pawn

    Board fact: Black moves the pawn from f7 to f6; from there it controls e5.

    Fixed engine check: Recorded move; a6 ranked higher · f6 d6+.

  29. 25.Rfd1 Improve the rook

    Board fact: White moves the rook from f1 to d1; from there it controls d4 and d3.

    Fixed engine check: Near the leading choice · Rfd1 Nd6 Ba3 Re2.

  30. 25...Qf5 Create pressure on d5

    Board fact: Black moves the queen from d7 to f5; from f5 it attacks White's pawn on d5 and White's pawn on f2.

    Fixed engine check: Near the leading choice · Qf5 d6+.

  31. 26.d6+ A forcing check

    Board fact: White moves the pawn from d5 to d6; the move checks Black's king; the pawn is now passed.

    Fixed engine check: Ranked first · d6+ Kh7 f3 Ng3.

  32. 26...Kh8 Answering the check

    Board fact: Black answers the check by moving the king from g8 to h8; from h8 it reinforces the pawn on g7.

    Fixed engine check: Ranked first · Kh8 f3 Ng3 Kh2.

  33. 27.f3 Create pressure on e4

    Board fact: White moves the pawn from f2 to f3; from f3 it attacks Black's knight on e4.

    Fixed engine check: Ranked first · f3 Ng3 Kh2 Ne2.

  34. 27...Ng5 Create pressure on f3

    Board fact: Black moves the knight from e4 to g5; from g5 it attacks White's pawn on f3 and White's pawn on h3.

    Fixed engine check: Playable; Ng3 ranked higher · Ng5 d7.

  35. 28.Rd5 Create pressure on f5

    Board fact: White moves the rook from d4 to d5; from d5 it attacks Black's queen on f5 and Black's pawn on b5.

    Fixed engine check: Recorded move; d7 ranked higher · Rd5 Qf4.

  36. 28...Qf4 Create pressure on d6

    Board fact: Black moves the queen from f5 to f4; from f4 it attacks White's pawn on d6 and White's pawn on f3.

    Fixed engine check: Ranked first · Qf4.

  37. 29.Qc2 Reposition the queen

    Board fact: White moves the queen from b3 to c2; from there it controls e4, c3 and c4.

    Fixed engine check: Near the leading choice · Qc2 Qg3.

  38. 29...Qg3 Create pressure on d6

    Board fact: Black moves the queen from f4 to g3; from g3 it attacks White's pawn on d6 and White's pawn on f3.

    Fixed engine check: Ranked first · Qg3 Kh1 Nxf3 gxf3.

  39. 30.Kh1 Reposition the king

    Board fact: White moves the king from g1 to h1; from h1 it reinforces the pawn on g2.

    Fixed engine check: Ranked first · Kh1 Nxf3 gxf3 Qxh3+.

  40. 30...Re1+ A forcing check

    Board fact: Black moves the rook from e8 to e1; the move checks White's king; the rook now occupies the open e-file; from e1 it attacks White's rook on d1.

    Fixed engine check: Recorded move; Nxf3 ranked higher · Re1+.

  41. 31.Rxe1 Answering the check

    Board fact: White's rook takes the rook on e1; the rook now occupies the open e-file; from e1 it reinforces the king on h1; white is ahead by 5 conventional material points after the capture.

    Fixed engine check: Ranked first · Rxe1 Qxe1+.

  42. 31...Qxe1+ Recapture on e1

    Board fact: Black's queen recaptures the rook on e1; the move checks White's king; material is level after the capture.

    Fixed engine check: Ranked first · Qxe1+.

  43. 32.Kh2 Answering the check

    Board fact: White answers the check by moving the king from h1 to h2; from h2 it reinforces the pawn on g2.

    Fixed engine check: Ranked first · Kh2 Ne6 d7 Nf4.

  44. 32...Qe8 Reposition the queen

    Board fact: Black moves the queen from e1 to e8; from there it controls e4, e5 and c6.

    Fixed engine check: Playable; b4 ranked higher · Qe8 Qd3 Ne6 Bc1.

  45. 33.Qc7 Create pressure on d8

    Board fact: White moves the queen from c2 to c7; from c7 it attacks Black's rook on d8 and Black's pawn on a7.

    Fixed engine check: Ranked first · Qc7.

  46. 33...Rd7 Rook on the semi-open d-file

    Board fact: Black moves the rook from d8 to d7; the rook now works on a semi-open d-file; from d7 it attacks White's queen on c7 and White's pawn on d6.

    Fixed engine check: Ranked first · Rd7.

  47. 34.Qc6 Create pressure on d7

    Board fact: White moves the queen from c7 to c6; from c6 it attacks Black's rook on d7 and Black's pawn on b5.

    Fixed engine check: Ranked first · Qc6 b4 Bd4 Nf7.

  48. 34...Qe6 Create pressure on d5

    Board fact: Black moves the queen from e8 to e6; from e6 it attacks White's rook on d5 and White's pawn on d6.

    Fixed engine check: Playable; b4 ranked higher · Qe6 Qxb5.

  49. 35.Qxb5 Exchange on b5

    Board fact: White's queen takes the pawn on b5; from b5 it attacks Black's rook on d7; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Qxb5 Nf7 Ba3 g5.

  50. 35...Nf7 Create pressure on d6

    Board fact: Black moves the knight from g5 to f7; from f7 it attacks White's pawn on d6.

    Fixed engine check: Ranked first · Nf7 Ba3 g5 Qd3.

  51. 36.Ba3 Reposition the bishop

    Board fact: White moves the bishop from b2 to a3; from there it controls c5 and d6.

    Fixed engine check: Ranked first · Ba3 g5 Qd3 Kg7.

  52. 36...Kh7 Reposition the king

    Board fact: Black moves the king from h8 to h7; from h7 it reinforces the pawn on g7.

    Fixed engine check: Ranked first · Kh7 Qd3+.

  53. 37.Qd3+ A forcing check

    Board fact: White moves the queen from b5 to d3; the move checks Black's king; from there it controls d4, d5 and e4.

    Fixed engine check: Ranked first · Qd3+ Kh8 h4 Qe1.

  54. 37...g6 Answering the check

    Board fact: Black answers the check by moving the pawn from g7 to g6; from there it controls f5.

    Fixed engine check: Near the leading choice · g6 Bb4 Kg7 f4.

  55. 38.f4 Advance the f-pawn

    Board fact: White moves the pawn from f3 to f4; from there it controls e5.

    Fixed engine check: Ranked first · f4 Kg7.

  56. 38...f5 Advance the f-pawn

    Board fact: Black moves the pawn from f6 to f5; from there it controls e4.

    Fixed engine check: Playable; Kg7 ranked higher · f5 Bb4 Kg7 Qd4+.

  57. 39.Bb2 Reposition the bishop

    Board fact: White moves the bishop from a3 to b2; from there it controls d4, e5 and c3.

    Fixed engine check: Ranked first · Bb2 Nd8 Ba3 Qe4.

  58. 39...Nd8 Reroute the knight

    Board fact: Black moves the knight from f7 to d8; from there it controls c6 and e6.

    Fixed engine check: Ranked first · Nd8 Bc3 Qe4 Qxe4.

  59. 40.Qc3 Reposition the queen

    Board fact: White moves the queen from d3 to c3; from there it controls d4, e5 and c4.

    Fixed engine check: Ranked first · Qc3 Qg8 Rc5 Rf7.

  60. 40...g5 Create pressure on f4

    Board fact: Black moves the pawn from g6 to g5; from g5 it attacks White's pawn on f4.

    Fixed engine check: Playable; Qg8 ranked higher · g5 Re5 Qf7 Rxf5.

  61. 41.Rxf5 Exchange on f5

    Board fact: White's rook takes the pawn on f5; from f5 it attacks Black's pawn on g5; white is ahead by 2 conventional material points after the capture.

    Fixed engine check: Near the leading choice · Rxf5 Rf7 Rxf7+ Qxf7.

  62. 41...Qg8 Create pressure on a2

    Board fact: Black moves the queen from e6 to g8; from g8 it attacks White's pawn on a2.

    Fixed engine check: Playable; Rf7 ranked higher · Qg8 Rf6 Kg7 fxg5.

  63. 42.Re5 Rook on the open e-file

    Board fact: White moves the rook from f5 to e5; the rook now occupies the open e-file; from e5 it attacks Black's pawn on g5.

    Fixed engine check: Recorded move; Rf6 ranked higher · Re5 Qf7 Re7 Rxe7.

PGN

[Event "London"] [Site "?"] [Date "1851.??.??"] [White "Anderssen, Adolf"] [Black "Szen, Jozsef"] [Result "1-0"] 1. e4 e6 2. d4 d5 3. exd5 exd5 4. c4 Bb4+ 5. Nc3 Qe7+ 6. Be3 Nf6 7. h3 Be6 8. Qb3 dxc4 9. Bxc4 Bxc4 10. Qxc4 c6 11. Nf3 Nbd7 12. O-O O-O 13. Rae1 Qe6 14. Ne5 Bxc3 15. bxc3 Nd5 16. Bc1 Rfe8 17. Nxd7 Qxd7 18. Qb3 h6 19. c4 Nf6 20. Rd1 Rad8 21. Bb2 b5 22. cxb5 cxb5 23. d5 Ne4 24. Rd4 f6 25. Rfd1 Qf5 26. d6+ Kh8 27. f3 Ng5 28. Rd5 Qf4 29. Qc2 Qg3 30. Kh1 Re1+ 31. Rxe1 Qxe1+ 32. Kh2 Qe8 33. Qc7 Rd7 34. Qc6 Qe6 35. Qxb5 Nf7 36. Ba3 Kh7 37. Qd3+ g6 38. f4 f5 39. Bb2 Nd8 40. Qc3 g5 41. Rxf5 Qg8 42. Re5 1-0

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:ea8c4dbc6dae39cefa9b148893d4c60adb9c40406852ea1b6072b6e837ea8247 and pins it in the selection manifest.
Exact Figshare tags:
White="Anderssen, Adolf"; Black="Szen, Josef"; Event="London knockout"; Date="1851.??.??"; Result="1-0".
Reviewed display mapping: black Szen, Josef → Szen, Jozsef; event London knockout → London. 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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