Game 38 in the book: a Sicilian Defence from the Winter-Tournament of the St. Petersburg Chess Society, March 1912, in which Alekhine plays Black against Potemkin and annotates his own win.

1. 2.g3 A good system of development against the Sicilian Defence, which was much favoured by Tchigorin. It has been adopted with success by Dr. Tarrasch in several Tournaments of recent years.
2. 5.c3 But the advance of P—Q 4, prepared by this move, is not in the spirit of this system. White should simply have developed his pieces by 5. Q Kt—B 3; 6. P—Q 3; 7. Castles, etc.
3. 6.Na3 This illogical move allows Black to obtain at once the superior game. It would certainly have been better to play 6. P—Q 4, P x P; 7. P x P, P—Q 3; although in this case also the White centre Pawns would have become weak.
4. 6…d5 Of course!
5. 9.d4 After this move the White Q P at once becomes weak. But 9. P—Q 3 was not much better.
6. 11.f3 The alternative 11. B—K 3 followed by Q—Q 2 and R—Q 1 was also unsatisfactory.
7. 11…Bf5 Threatening to win the Q P by B x Kt, etc.
8. 12…Qa5+ This last move prevents Castling, for after 13. Q—Q 2 or 13. B—Q 2 the answer 13. ....Kt x Kt wins a piece.
9. 13…Ndb4 Threatening amongst other things to win the Q P after B—Q 6.
10. 16…Nxd4 Decisive.
11. 17.gxf5 For if 17. Kt x Kt, Q—K 4 ch, etc., would give Black an easy win.
12. 17…Nxf5+ and mates in two. If 18. K—Kt 4, P—R 4 ch and mate next move by the B or the Kt. If 18. K—R 3, Kt—B 7, a "pure mate."