visayanbraindoctor: <paladin at large: A masterful queen ending by Bernstein, worthy of Maróczy. Not a bad master over the age of 50 who can draw a four game match with Alekhine in his prime.>
Surprise! I did not know Alekhine played a match while still a reigning World Champion. Does anyone know about the details of this match?
After 16. Qe3, AAA offers his a7 pawn with 16.. e4
(So typical of Alekhine, the master of a thousand sacs. How in the world is he able to consistently sac material game after game, and more importantly create positions that make such sacs feasible?)
Bernstein grabs it. 17. dxe4 Rxe4 18. Qxa7
After 18. Qxa7 Bxf3 19. gxf3 Rxe1+ 20. Bxe1 Nb6
We see AAA's point. He blocks off the White Queen on a7. Typical of such Q grabs RP sacs, Black obviously was planning to isolate the White Queen in the Queenside and deploy an attack against the White King on the other side of the board.
But Bernstein counters with
Alekhine probably missed this in his calculations, or saw it but thought he still had compensation. It deflects the Back Queen away from the c7 Black pawn. 21...Qxc5 is answered by the skewer 22. Bb4
AAA proceeds with his Kingside plans by moving his Queen to an attacking position in the Kingside, but Bernstein wisely exchanges off the rooks.
21. c5 Qg6+ 22. Kf1 Nd5 23. Rb8 Qh5 24. Rxf8+ Kxf8
Had Black been able to swing this Rook over to the Kingside it would have been curtains for White. Bernstein nips it off in the bud.
Bernstein next gives up his KRP in order to gain tempi to bring back his off-place Queen into the game.
25. Qb8+ Ke7 26. Qb3 Qxh2
Now Black threatens to directly attack the White King by Nf4.
But 27. Bd2 contains the Knight.
Now suddenly it's an endgame where the inconspicuous extra White a-pawn is now a potentiality dangerous outside passer. Bernstein proceeds to push it of course.
27. Bd2 Qh1+ 28. Ke2 Qa1 29. c4 Qe5+ 30. Kf1 Nf6 31. Bc3 Qe6 32. a4 g5 33. a5 g4 34. a6 gxf3
The Queen + Knight combination is a superb attacking weapon, and Bernstein exchanges the Knight off.
35. Bxf6+ Qxf6
He then proceeds to demonstrate the power of the outside passed pawn in a Queen endgame. As with all top class masters, he knew Queen endgames are often won by the outside passed pawn.