Game 170 in Philip W. Sergeant’s Morphy’s Games of Chess (1916), printed pages 229–230. Commentary from this edition; named earlier annotators remain credited in the notes. The source dates this game New York, 1857; the archive dates it 1858.

1. 10.Bf4 The form of the Lopez Defence in this game is one seldom seen nowadays. Morphy claimed his 10th move as “an improvement on that given in the leading treatises of the day,” viz. 10 Q×P (as in Hanstein–v. d. Lasa, Staunton’s “Handbook,” p. 151). It is certainly more characteristic of Morphy to develop a piece and keep his opponent on the defensive, rather than spend time in recapturing a Pawn which remains indefensible.
2. 18…Qf6 Black cannot otherwise save his KBP.
3. 23…Rh8 If P—R5, 24 R—Kt3ch, K—R1; 25 B×BP.
4. 30.Rdg4 “Winning by force,” says Morphy. “This game has certainly no claims to brilliancy, but illustrates the difficulty of a correct defence to the Ruy Lopez game” (A.C.M., March 1858, p. 86). Maroczy, however, claims the game as one of Morphy’s best performances, owing to the iron precision of the moves.