4…c5When this advance is made prematurely, the isolation of the Queen's Pawn is the necessary consequence.
7…Nc6This gets Black into difficulties. 7) ..., B - K 2 was indicated. If then 8) P - K 3, O - O, exception could scarcely be taken to Black's position.
9.Bb5This move shows why Black's 7th was open to censure.
10.Bxf6The gain of the Pawn is only temporary. 10) O - O would have been stronger, as the Queen's Pawn would have fallen afterwards in any case.
14…O-O-OA careless move. Black should not have given up his intention to win the Knight's Pawn, simply because White had omitted the check at K 2.
16.Rc1A move of extraordinary subtlety. White now retains his advantages. He threatens R - B 5 and P - Q 5, and Black's obvious threat of R x Kt he meets as is shown by his 17th move.
16…Rxe3Also after 16) ..., K - Kt 1 Black would have a bad position.
18…Rxd4A better chance was offered by 18) ..., R - K 4.
21.Rf4A splendid conception. He threatens Q - R 8 ch, followed by R - K 4 or R - Q B 4 ch, winning the game by the attack. Black's only alternative is to exchange Queens and lose the end game.
Emanuel Lasker, The International Chess Congress, St. Petersburg, 1909 (1910) · Public domain · source