Monday, January 30, 2017

The Dutch Defense

1. d4 f5 2. g3

The most common move, and the most successful. White has an 18% edge.

Nf6 3. Bg2 g6

Black is at something of a crossroads here, as he must decide where to put his King Bishop. 3...g6 is preferred by almost 3-1 over 3...e6, after which the usual continuation is  4. Nf3 Be7 5. O-O O-O 6. c4 d6 7. Nc3 Qe8, and now Qc2, Rel, and b3 are about equally played; however, the biggest advantage is with 8 b3, which enjoys a huge 33% edge over black!

4. Nf3 Bg7 5. 0-0 O-O 6. b3 d6 7. Bb2

An advantage of this line for white is that it is easy to remember. You simply fianchetto both bishops! White's advantage now is a huge 22%!

7...Qe8

The most popular of the 17(!!) different moves that have been played here.

8. c4 Na6 9. Nbd2 e5 10. dxe5 Ng4 11. Ba3 Nxe5 12. Nxe5 Qxe5 13. Rb1 Qe7 14. b4 Rb8 15. Nb3 Be6 16. Na5 c5 17. bxc5 Nxc5 18. Bxc5 dxc5 19. Bxb7 Qc7 20. Bd5 Qxa5 21. Bxe6+ Kh8 22. Qc2 Rb6 23. Rxb6 Qxb6 24. Bd5 Rb8 25. Qa4 Rd8 26. e3 Be5 27. Kg2 Qf6 28. Rd1 Kg7 29. Rd3 Qe7 30. Rb3 Rb8 31. Ra3 Rb2 32. Qxa7 Qxa7 33. Rxa7+ Kh6 34. Bg8 1-0

Monday, January 9, 2017

The Exchange Variation of the Gruenfeld Defense

1 d4 Nf6 2 c4 g6 3 Nc3 d5 4 cxd5

I now prefer this move to my old favorite, 4 Bg5, the Stockholm variation. 4 cxd5 is preferred by 3-2 over 4 Nf3, the next most popular move.

4...Nxd5 5 e4 Nxc3

5...Nb6 6 Be3 Bg7 7 h3 0-0 8 Nf3 Nc6 9 Be2 f5 10 ef Bxf5 11 Qb3+ Kh8 12 Rd1 is fine for white.

6 bc Bg7 7 Bc4 c5 8 Ne2 0-0

8...Qa5 9 0-0 is good for white.

9 Be3 Nc6 10 0-0 Bg4 11 f3 Na5

11...Bd7 actually scores well for black, but 11...Na5 is preferred by 5-1. A sample game with 11...Bd7 ran 11.... Bd7 12. Rb1 Qc7 13. Qd2 Rad8 14. Rfc1 Bc8 15. Bh6 Bxh6 16. Qxh6 cxd4 17. cxd4 Qd6 18. e5 Qd7 19. Bb5 Qd5 20. Bc4 Qd7 21. Bb5 Qe6 22. Bc4 Qd7 23. Bb5 1/2-1/2

12  Bd3 cd 13 cd Be6

13...Bd7 seems to have the advantage over 13...Be6 by saving a tempo. However, white gets an advantage after each of the three responses. a) 14. Rb1 b6 15. Qd2 Rc8 16. Rfc1 Bc6 17. Ba6 Bb7 18. Bxb7 Nxb7 19. Rxc8 Qxc8 20. Rc1 Qd7 21. Qc2 h6 22. Qc7 Rd8 23. Kf2 e6 24. Qxd7 Rxd7 25. Rc8+ Nd8 26. Ke1 Kf8 27. Kd2 Ke7 28. Kc2 Rd6 29. Rc7+ Rd7 30. Rc8 Rb7 31. Bf4 Kd7 32. Rb8 Rxb8 33. Bxb8 Nc6 34. Bf4 Nxd4+ 35. Nxd4 Bxd4 36. Bxh6 b5 37. Kd3 Bb2 38. Be3 a5 39. Bb6 a4 40. Ba5 Kc6 41. Bb4 Be5 42. h3 Bc7 43. Kd4 1/2-1/2  b) 14. Rc1 Rc8 15. Qd2 a6 16. d5 b5 17. Rxc8 Bxc8 18. Rc1 Bb7 19. Nd4 Bxd4 20. Bxd4 e6 21. Qe3 f6 22. e5 exd5 23. exf6 Qe8 24. f7+ 1-0, or c)  14. Qd2 Rc8 15. Rac1 a6 , transposing into the last game. White gets an easy game in all these lines with simple, stock moves.

14 d5

Here is the main idea; white sacs the exchange for a King-side attack. 14 Rc1 is an alternative, but the complications after 14...Bxa7 are not very interesting or productive for white.

14...BxR 15 QxB f6

White cannot play 16 de due to 16...Qxd3, so black immediately shores up his dark square defenses.

16 Bh6 Re8 17 Kh1 (not 17 Bb5? Qb6+) Rc8 18 Nf4

Here and in the next few moves white proceeds very aggressively, in order to justify his sac of the exchange.

18...Bd7 (not 18...Bf7 19 Bb5) 19 e5 Nc4 20 e6 Ba4

20...Bb5 is also playable. One game continued:   21. Qe1 Nd6 22. Bxg6 hxg6 23. Qg3 Bd3 24. Nxd3 Kh7 25. Nf4 Rg8 26. Qh3 Rh8 27. Bf8+ Kg8 28. Bxe7 Qxe7 29. Qxh8+ Kxh8 30. Nxg6+ Kg7 31. Nxe7 Rc7 32. f4 Rxe7 (white has 3 pawns for a knight) 33. Rc1 f5 34. h3 Ne4 35. Kg1 Nf6 36. Rd1 Re8 37. d6 Rd8 38. g4 fxg4 39. hxg4 Kg6 40. g5 Kf5 41. e7 Rg8 42. d7 Nxd7 43. Rxd7 Re8 44. Kf2 b5 45. Kf3 a6 46. Rd6 1-0 The database shows about the same ratio of wins for black and white for Bb5 as for the more usual move of Ba4, but almost twice as many draws!

Instead of the defensive move 23...Bd3, Black has tried 23...g5. There might follow 24. Bxg5 Nf5 25. Qg4 Ne3 26. Qh5 Bd3 27. Ng6 Bxg6 28. Qxg6+ Kh8 29. Qh5+ Kg8 30. Bh6 Nf5 31. Qxf5 Kh8 32. Qh5 1-0) If black tries 24...fg, taking the Bishop, There follows 25 Qxg5+ Kh7 26 Qg6+ Kh8, 27 Qh6+ Kg8 28Ng6 Nf7 29 ef+ Kxf7 30 Ne5+ Kg8 32 Qg6+ Kh8 33Nf7#.  Or, if black tries 26...Bxf1, there follows 27Qf7+ Kh8 28 Ng6#.

21 Nxg6!

William Hartston, in his 1971 book on the Gruenfeld, does not mention this move, which was apparently unknown at the time. He gives a 1955 game in which Gligoric lost as white as evidence that this line is bad for white. That game continued 21Qe1 Ne5 22 Qg3 Qd6 23 Be4 Bc2 24 h4 Kh8 25 Nh5 Rg8 26 Nxf6 ef 27 Bf4 b5 28 Re1 Rg7 29 Rc1 Rgc7 30 Bxe5 fe 31 Bxc2 Rxc2 32 Rxc2 Rxc2 33 Qg5 Rc7 34 h5 gh 35 Qf6+ Rg7 36 Qf5 a5 37 Qxh5 Qxd5 38 Qe8+ Rg8 39 Qf7 Qd1+ 40 Kh2 Qd6 41 Qf6+ Rg7 42 g4 e4+ 43 f4 Qd2+ 44 Kg1 Qe1+ 0-1

A database check reveals that 21 Nxg6 wins for white 53% of the time, to only 21% wins for black.

hg 22 Bxg6 Ne5

22... Kh8 was played only twice in my usual database, but black won both of these games after long struggles, beginning with neutralizing white's king-side attack with 23. Qe1 Rg8 24. Be4 Be8 25. Qh4 Rg6 26. Qh5 Ne5 27. Bf4+ .  However, further inquiry reveals that 27 f4, instead of Bf4+, gives white the advantage, and black must finagle for the draw. Also, the computer likes 24...Qe8, instead of the awkward 24...Be8, but here again, black must fight for the draw.

(3/9/20 update)  I found a game in which 27 f4 fizzled out to a quick draw:  27 f4 Rc4 28 Bb1 Rxg2 (the only move which saves the game for black) 29 Bg7+ KxB 30 Qh7+ drawn.

The tempting 22...Qxd5 simply loses to 23 Qe1. There follows 23...Qe5 24 Qh4 (not 24 Bf7+, which only draws) Qxe6 25 Bxe8 Ne5 26 Qg3+ Ng4 27 Bxa4 Kh7 28 Re1 winning. Or, 23...Ne5 24 Qg3 Kh8 25 Bxe8 Ng4 26 Qxg4 1-0. Or, 23...Ne5 24 Qg3 Kh8 25 Bxe8 Ng4 26 Qxg4 1-0

(7/10/20 update)  Against player "tfee" I forgot the line when he played 22...Qxd5.  Play continued 23 Qe1 Qe5, but here I blundered with 24 Bf7+.  Fortunately, tfee blundered back with 24...Kh7, and I was able to finish him off with 25 Qh4 Rh8 26 Bf8+ Qh5 27 QxQ#.  Black's drawing line was 24...Kh8! 25 Qh4 Qf5! 26 Bxf6+ ef 27 Qxf6+ Qg7 28 Qh4+ Qh7, and white must repeat moves as the mate is gone and he is down a rook.

Going back to the position after 22 Bxg6, player "More" on 7/10/20 was the first player to play the star move of 22...Kh8 against me.  Play continued correctly with 23 Qe1 Rg8, but then I blundered with 24 Bf7, and my game fell apart.  I need to remember, Be4, not Bf7!

23 Be4 Bc2 24 BxB RxB 25 Qd1 Kh7

The only move which meets white's threat of 26 f4 followed by queen to g4 or h5. 25,,,Qc7 26 f4 Kh7 simply transposes.

26 f4 KxB 27 fe Qc7 28 ef Rf8

28...ef 29 Qd4 Kh7 30. Qh4+ Kg8 31. Qxf6 Ra8 32. e7 Kh7 33. Qf5+ Kh6 34. Qe6+ Kg5 35. Rf5+ Kg4 36. Qe4+ 1-0

The idea of ganging up on the c-file doesn't work: 28...Rc8 29 f7 Rc1 30 f8(Q) RxQ 31 QxR/1+ and white is two pawns up.

28...Qc4 29 f7 Rf1 simply transposes.

29 f7 Qc4 30 d6 ed 31 Re1

Or  31. e7 Rxf7 32. Qxd6+ Kh7 33. Rxf7+ Qxf7 34. Qd3+ Kg7 35. Qd4+ Kg8 36. Qd8+ Kg7 37. Qd4+ drawn

31...Rf2!

Adroitly combining offense and defense.

32 h3 d5

An entertaining line is  32...Rc8 33 Qxd6 Rf1+ 34. Kh2 Kh7 35. e7 Rxf7 36. e8=Q Rxe8 37. Rxe8 Qxa2 38. Qd3+ Kh6 39. Qe3+ Kh7 40. Qe4+ Kh6 41. Rg8 Rg7 42. Qh4+ Kg6 43. Qg4+ Kf6 44. Qxg7+ 1-0

33 a4 

More straightforward is 33 e7 R8xf7 (33...R2xf7 34 Qd2+ Kh7 35 ef(N)+ RxN 36 Re7+ Kg6 37 Rxb7 +1.15) 34 e8(Q) Rf1+ 35 RxR RxR+ 36 QxR QxQ+ 37 Kh2 drawn.

d4 34 Kg1 R2xf7 

Black elects to give up his extra rook for white's extra two pawns. To be considered was 34...Qa2.

35 ef Rxf7 36 Re4 Rf5 

Trying to save the d-pawn with 36...Rd7 loses to 37 Rh4+ Kg7 38 Qg4+ and the rook falls.

37 Qd2+ Kg6 38 Rg4+ Kf7 39 Qxd4 Rf1+ 40 Kh2 Qc7+ 41 Rg3 Rf6 42 Qg4 Ke7 43 h4 a6 44 Kh3 Qc1 

Computer analysis suggests that this is where black goes wrong. The computer suggests 44...Qd7, although the resulting rook-and-pawn endgame should be easily won for white.

45 Qg7+ Ke6 46 Qg8+ Ke7 47 Rg7+ Kd6 48 Qd8+ Ke6 49 Qd7+ Ke5 50 Re7+  1-0