Queen's Indian Defense, Classical Variation - Polugayevsky Gambit

GARRY KASPAROV vs. SLAVOLJUB MARJANOVIC
Malta 1980

1. d4, Nf6
2. c4, e6
3. Nf3, b6
4. g3, Bb7
5. Bg2, Be7
6. 0-0, 0-0
7. d5!, exd5
8. Nh4 ....

The Polugayevsky Gambit.  White sacrifices a pawn to secure the f5 location for the King's Knight.

8. .... c6
9. cxd5, Nxd5
10. Nf5!, Nc7
11. Nc3, d5
12. e4! ....

This sharp move intends to weaken Black's central pawn structure.

12. .... Bf6
13. exd5, cxd5
14. Bf4, Nba6
15. Re1 ....

Taking control of the e-file.

15. .... Qd7
16. Bh3, Kh8

Black avoids the disastrous Nh6+.

17. Ne4!!, Bxb2
18. Ng5, Qc6?

Black intends to threaten mate at h1, but only manages to displace the Queen.

19. Ne7, Qf6
20. Nxh7 ....

The Knight cannot be taken because 21. Qh5+ threatens mate.

20. .... Qd4
21. Qh5, g6
22. Qh4, Bxa1
23. Nf6 dis chk, Resigns

After 23....Kg7, there are several ways of mating Black.  One line is 24. Qh6+ Kxf6, 25. Bg5 mate.

Another line is 24. Bh6+ Kh8 (or Kh7), 25. Bxf8 mate.