Dana's Bio


News & Events



Mackenzie,Dana - Pruess,David [B21]
Western States Open, 08.10.2006

Note: This game also appears in Chess Life, March 2007. To avoid duplication, I have kept the notes somewhat brief. For more details on this game, read my article, "Sac Your Queen on Move Six! (A New Anti-Computer Variation)."

1.e4 c5 2.f4 d5 3.Nf3!? ...

White offers a pawn sacrifice, turning the position into a Budapest Defense with colors reversed! White's extra tempo has been used to play f2-f4, so the big question is whether this move helps White or hurts him.

3...dxe4 4.Ng5 Nf6 5.Bc4 Bg4?!

A completely sound alternative for Black is 5...e6 6.Nc3, where White wins back the pawn, but cannot claim any real advantage. However, IM Pruess refuses to be intimidated by my threats against f7, and threatens to win my queen. What can White do?

6.Qxg4!! ...

I first started playing this queen sacrifice in 2004, as a crazy experiment against Fritz, the computer chess program. After playing perhaps a hundred games with it over two years against the computer, I believe that the queen sacrifice is completely sound. It is far too complex, however, for an exhaustive analysis, which makes it an ideal weapon to play against the computer. This game proves that it works pretty well against humans, too!

6...Nxg4 7.Bxf7+ Kd7 8.Be6+ Kc6 9.Bxg4 e6

An important trap is 9...e5? 10.Nf7 Qh4+ 11.g3 Qxg4?? 12.Nxe5+ and Black resigned (Mackenzie vs. Drayton Harrison, Western States Open, 2006). This was my very first tournament game with the Queen Sacrifice Variation, two days before the game with Pruess.

10.Nc3 Na6 11.a3! ...

It's amazing that White, with only two pieces for a queen, can afford to play such a calm, defensive move. But it's important to realize that White's strategy is not based on speedy attack; it is based on coordinating his pieces and taking away all of Black's possibilities for counterplay.

11...Bd6 12.0-0 Nc7 13.Ncxe4 Qe7 14.Nxd6 Qxd6 15.d3 Raf8 16.Bf3+ Kd7 17.c3!? Nd5 18.g3 h6 19.Ne4 Qc7 20.b4!


After this move I was sure that White was gaining the upper hand.


20. ... b6 would put up stiffer resistance. The text move opens new lines for White's pieces and leaves Black with no solid outposts in the center.

21.axb4 b6 22.Bd2 Rf7 23.c4 Nf6 24.Bc3 Ke7?

This was Black's only clear mistake of the game. 24...Nxe4 25.Bxe4 Ke7 26.Be5 is very unappetizing for Black, but at least he only has to contend with two White minor pieces. In the game, he has to face three -- the two bishops and the knight.

25.Be5 Qd7 26.Nd6 ...


Complete domination by White's minor pieces!


Now if Black tries to exchange knights with 26...Ne8 he runs into 27.Rxa7! Also, if he tries to give back his queen with 26. ... Qxd6 27. Bxd6+ Kxd6, he will end up two pawns behind after 28. Ra6 and 29. c5+.

27.Nxf7 Kxf7 28.d4 Kg6?!

Black should try to create some counterplay with 28...b5 29.c5 Nd5. However, after 30.Rfb1 White still has a big advantage. White's idea is to play 31. Ra6 next move, and if Black tries to prevent it with 30. ... Qb7, he puts his knight into a pin. Thus White can continue with 31. Ra3 followed by 32. Rba1.

29.g4 Rc8 30.c5 Qb5 31.Rxa7 Qd3

If 31...Qxb4? 32.Be4+ Nxe4 33.Rxg7 mate. Things are starting to heat up around Black's king!

32.h4 h5 33.g5 Ne8

After the game Pruess thought that he had missed a draw with 33...Ng4!? The idea is that White will be forced to accept a perpetual check on g7 and f7 because Black's threats on the kingside are too strong. However, White has an amazing reply:


Position after 33. ... Ng4 (Analysis)

34.f5+!! Black has three ways to take the pawn, all of them bad. If Black takes with the pawn or queen, his king has no flight squares left, so 35. Rxg7 is mate. If he takes with the king, he walks into a monster discovered check that wins the queen. And finally, 34...Kh7 allows 35.Rxg7+ Kh8 36.Bxg4. Note the final twist of White's pawn move -- it cleared the way for White's bishop on e5 to defend g3, thus depriving Black of the opportunity for a perpetual check.

34.Kg2 b5 35.Re1 Kf5 36.Be4+ ...

Thirty moves after his queen sacrifice, White wins back the queen with interest! The rest of the game is easy, though I did have to avoid a couple of tricks.

36...Qxe4+ 37.Rxe4 Kxe4 38.Ra5 Nc7 39.Bxg7 Kxf4 40.Be5+ Kg4 41.g6 Kxh4 42.g7 Rg8 43.Ra7 Nd5 44.Rf7 Ne3+ 45.Kf3 Ng4 46.c6 1-0

Copyright Notice

All text on this website is Dana Mackenzie.

Image copyrights may belong to other people or organizations. Contact me for further information.