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Classic game replay

Paul Morphy vs NN, 1858

This replay preserves the complete 45-ply score of Morphy playing White across 23 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
Paul Morphy
Black
NN
Event
New Orleans sim
Year
1858
Result
1-0
Opening
C56 Italian Game: Two Knights Defense, Perreux Variation

Opening reference: Italian Game: Two Knights Defense, Perreux Variation (C56).

In this game, 20 half-moves are labelled opening, 25 middlegame and 0 endgame. The score contains 13 captures and 11 checks or mates; before a recorded move, the position offered a median of 35 legal choices. The final recorded move is 23.Rb1#, which is checkmate; the stored result is 1-0.

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. 6.exd5 — Exchange on d56.exd5 was a leading choice in the fixed engine check.
  2. 14.Rxe5+ — Recapture on e514.Rxe5+ was a leading choice in the fixed engine check.
  3. 18.b4+ — A forcing check18.b4+ was a leading choice in the fixed engine check.
  4. 23.Rb1# — Checkmate23.Rb1# 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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Paul Morphy vs NN, 1858

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...dxc3

  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...e5 Claim central space

    Board fact: Black moves the pawn from e7 to e5; from there it controls d4 and f4.

    Fixed engine check: Ranked first · e5 Nf3 Nc6 d4.

  3. 2.Nf3 Develop the knight

    Board fact: White develops the knight from g1 to f3; from f3 it attacks Black's pawn on e5.

    Fixed engine check: Ranked first · Nf3 Nc6 d4 exd4.

  4. 2...Nc6 Develop the knight

    Board fact: Black develops the knight from b8 to c6; from there it controls d4 and e5.

    Fixed engine check: Ranked first · Nc6 d4 exd4 Nxd4.

  5. 3.Bc4 Develop the bishop

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

    Fixed engine check: Ranked first · Bc4 Nf6 d3 d6.

  6. 3...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 Ng5.

  7. 4.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 e5.

    Fixed engine check: Ranked first · d4 exd4 e5 d5.

  8. 4...exd4 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 · exd4 e5 d5 Bb5.

  9. 5.Ng5 Create pressure on f7

    Board fact: White moves the knight from f3 to g5; from g5 it attacks Black's pawn on f7 and Black's pawn on h7.

    Fixed engine check: Playable; e5 ranked higher · Ng5 d5 exd5 Qe7+.

  10. 5...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 bishop on c4 and White's pawn on e4.

    Fixed engine check: Ranked first · d5 exd5 Qe7+ Kf1.

  11. 6.exd5 Exchange on d5

    Board fact: White's pawn takes the pawn on d5; the move changes the central pawn contact; from d5 it attacks Black's knight on c6; material is level after the capture.

    Fixed engine check: Ranked first · exd5 Qe7+.

  12. 6...Nxd5 Recapture on d5

    Board fact: Black's knight recaptures the pawn on d5; from d5 it reinforces the pawn on c7; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Recorded move; Qe7+ ranked higher · Nxd5 O-O Be7 Nxf7.

  13. 7.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 Be7 Nxf7 Kxf7.

  14. 7...Be7 Develop the bishop

    Board fact: Black develops the bishop from f8 to e7; from e7 it attacks White's knight on g5.

    Fixed engine check: Ranked first · Be7 Nxf7 Kxf7 Qh5+.

  15. 8.Nxf7 Exchange on f7

    Board fact: White's knight takes the pawn on f7; from f7 it attacks Black's queen on d8 and Black's rook on h8; material is level after the capture.

    Fixed engine check: Ranked first · Nxf7 Kxf7 Qh5+ g6.

  16. 8...Kxf7 Recapture on f7

    Board fact: Black's king recaptures the knight on f7; from f7 it reinforces the bishop on e7; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Kxf7.

  17. 9.Qf3+ A forcing check

    Board fact: White moves the queen from d1 to f3; the move checks Black's king; from f3 it attacks Black's knight on d5.

    Fixed engine check: Ranked first · Qf3+ Ke8 Bxd5 Rf8.

  18. 9...Ke6 Answering the check

    Board fact: Black answers the check by moving the king from f7 to e6; from there it controls d5, e5 and d6.

    Fixed engine check: Recorded move; Bf6 ranked higher · Ke6 Re1+ Ne5 Bf4.

  19. 10.Nc3 Develop the knight

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

    Fixed engine check: Playable; Re1+ ranked higher · Nc3 dxc3 Re1+ Ne5.

  20. 10...dxc3 Exchange on c3

    Board fact: Black's pawn takes the knight on c3; the move changes the central pawn contact; Black accepts doubled pawns on the c-file; from c3 it attacks White's pawn on b2; black is ahead by 6 conventional material points after the capture.

    Fixed engine check: Ranked first · dxc3 Re1+.

Middlegame · 11.Re1+ to 23.Rb1#

  1. 11.Re1+ A forcing check

    Board fact: White moves the rook from f1 to e1; the move checks Black's king; the rook now occupies the open e-file; from there it controls e4, e5 and e3.

    Fixed engine check: Ranked first · Re1+ Ne5 Bf4 Bf6.

  2. 11...Ne5 Answering the check

    Board fact: Black answers the check by moving the knight from c6 to e5; from e5 it attacks White's queen on f3 and White's bishop on c4.

    Fixed engine check: Ranked first · Ne5 Bf4.

  3. 12.Bf4 Develop the bishop

    Board fact: White develops the bishop from c1 to f4; from f4 it attacks Black's knight on e5.

    Fixed engine check: Ranked first · Bf4 c6 Bxe5 Kd7.

  4. 12...Bf6 Reposition the bishop

    Board fact: Black moves the bishop from e7 to f6; from there it controls e5.

    Fixed engine check: Playable; c6 ranked higher · Bf6 Rxe5+ Bxe5 Re1.

  5. 13.Bxe5 Exchange on e5

    Board fact: White's bishop takes the knight on e5; from e5 it attacks Black's bishop on f6 and Black's pawn on c3; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Recorded move; Rxe5+ ranked higher · Bxe5 Bxe5.

  6. 13...Bxe5 Recapture on e5

    Board fact: Black's bishop recaptures the bishop on e5; from e5 it attacks White's pawn on h2; black is ahead by 6 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxe5 Rxe5+.

  7. 14.Rxe5+ Recapture on e5

    Board fact: White's rook recaptures the bishop on e5; the move checks Black's king; the rook now occupies the open e-file; from e5 it attacks Black's knight on d5; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Rxe5+ Kxe5 Re1+ Kd4.

  8. 14...Kxe5 Recapture on e5

    Board fact: Black's king recaptures the rook on e5; from e5 it reinforces the knight on d5; black is ahead by 8 conventional material points after the capture.

    Fixed engine check: Ranked first · Kxe5 Re1+.

  9. 15.Re1+ A forcing check

    Board fact: White moves the rook from a1 to e1; the move checks Black's king; the rook now occupies the open e-file; from there it controls e4, e5 and e3.

    Fixed engine check: Ranked first · Re1+ Kd4 Bxd5 cxb2.

  10. 15...Kd4 Answering the check

    Board fact: Black answers the check by moving the king from e5 to d4; from d4 it attacks White's bishop on c4.

    Fixed engine check: Ranked first · Kd4 Bxd5 Qf6 Rd1+.

  11. 16.Bxd5 Exchange on d5

    Board fact: White's bishop takes the knight on d5; from d5 it attacks Black's pawn on b7; black is ahead by 5 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxd5 Qf6 Rd1+ Kc5.

  12. 16...Re8 Rook on the open e-file

    Board fact: Black moves the rook from h8 to e8; the rook now occupies the open e-file; from e8 it attacks White's rook on e1.

    Fixed engine check: Recorded move; Qf8 ranked higher · Re8 Rd1+ Ke5 Qxc3+.

  13. 17.Qd3+ A forcing check

    Board fact: White moves the queen from f3 to d3; the move checks Black's king; from d3 it attacks Black's pawn on c3 and Black's pawn on h7.

    Fixed engine check: Ranked first · Qd3+ Kc5 b4+ Kxb4.

  14. 17...Kc5 Answering the check

    Board fact: Black answers the check by moving the king from d4 to c5; from c5 it attacks White's bishop on d5.

    Fixed engine check: Ranked first · Kc5 b4+ Kxb4 Qc4+.

  15. 18.b4+ A forcing check

    Board fact: White moves the pawn from b2 to b4; the move checks Black's king; from there it controls c5.

    Fixed engine check: Ranked first · b4+ Kxb4 Qc4+ Ka5.

  16. 18...Kxb4 Answering the check

    Board fact: Black's king takes the pawn on b4; from b4 it reinforces the pawn on c3; black is ahead by 6 conventional material points after the capture.

    Fixed engine check: Ranked first · Kxb4 Qc4+ Ka5 Qxc3+.

  17. 19.Qd4+ A forcing check

    Board fact: White moves the queen from d3 to d4; the move checks Black's king; from d4 it attacks Black's pawn on a7 and Black's pawn on c3.

    Fixed engine check: Ranked first · Qd4+ Ka5 Qxc3+ Ka4.

  18. 19...Ka5 Answering the check

    Board fact: Black answers the check by moving the king from b4 to a5.

    Fixed engine check: Ranked first · Ka5 Qxc3+ Ka4 Qb3+.

  19. 20.Qxc3+ Capture with check on c3

    Board fact: White's queen takes the pawn on c3; the move checks Black's king; from c3 it attacks Black's pawn on c7 and Black's pawn on g7; black is ahead by 5 conventional material points after the capture.

    Fixed engine check: Ranked first · Qxc3+ Ka4 Qb3+ Ka5.

  20. 20...Ka4 Answering the check

    Board fact: Black answers the check by moving the king from a5 to a4.

    Fixed engine check: Ranked first · Ka4 Qb3+ Ka5 Qa3+.

  21. 21.Qb3+ A forcing check

    Board fact: White moves the queen from c3 to b3; the move checks Black's king; from b3 it attacks Black's pawn on b7.

    Fixed engine check: Ranked first · Qb3+ Ka5 Qa3+ Kb6.

  22. 21...Ka5 Answering the check

    Board fact: Black answers the check by moving the king from a4 to a5.

    Fixed engine check: Ranked first · Ka5 Qa3+ Kb6 Rb1#.

  23. 22.Qa3+ A forcing check

    Board fact: White moves the queen from b3 to a3; the move checks Black's king; from there it controls c3, c5 and d3.

    Fixed engine check: Ranked first · Qa3+ Kb6 Rb1#.

  24. 22...Kb6 Answering the check

    Board fact: Black answers the check by moving the king from a5 to b6; from there it controls c5 and c6.

    Fixed engine check: Ranked first · Kb6 Rb1#.

  25. 23.Rb1# Checkmate

    Board fact: White's rook moves from e1 to b1 and delivers checkmate; Black's king has no legal way to answer the attack.

    Fixed engine check: Ranked first · Rb1#.

PGN

[Event "New Orleans sim"] [Site "?"] [Date "1858.??.??"] [White "Morphy, Paul"] [Black "NN"] [Result "1-0"] 1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. d4 exd4 5. Ng5 d5 6. exd5 Nxd5 7. O-O Be7 8. Nxf7 Kxf7 9. Qf3+ Ke6 10. Nc3 dxc3 11. Re1+ Ne5 12. Bf4 Bf6 13. Bxe5 Bxe5 14. Rxe5+ Kxe5 15. Re1+ Kd4 16. Bxd5 Re8 17. Qd3+ Kc5 18. b4+ Kxb4 19. Qd4+ Ka5 20. Qxc3+ Ka4 21. Qb3+ Ka5 22. Qa3+ Kb6 23. Rb1# 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:cfa964db7eacf676ca05268e2f9eff93c63720e2b75cb1f1ec39f2b177f297f2 and pins it in the selection manifest.
Exact Figshare tags:
White="Morphy, Paul"; Black="NN"; Event="New Orleans sim"; Date="1858.??.??"; Result="1-0". 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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