IM Mark Ginsburg Analyzes one of the many Critical Positions in the Scorpion-Mechanic USCL Match

Oct 15, 2009, 6:19 PM |

Scorpions-Mechanics: Not for the Faint of Heart

Wow, I am still freaking out a day later.  The Arizona Scorpions and the SF Mechanics played a titantic match on 10/14/09 that will go down in USCL annals as one of the most topsy-turvy matches ever.

I was really pleased to see David Adelberg play the Kan on board 4 for Arizona, consistent with my match preview! Although he got fatigued and eventually lost his way, I am very happy with how well the fearsome Kan did in the opening.

Here is Board 2’s madness.

IM John Donaldson (SF) – IM Dionisio Aldama (ARZ)

1.Nf3 Nf6 2.c4 g6 3.g3 Bg7 4.Bg2 0-0 5.0-0 d6 6.d4 Nc6 7.Nc3 a6 8.d5 Na5 9.b3 c5 10.dxc6 Nxc6 11.Bb2 Bd7 12.Qc1 Rc8 13.Nd5 Nxd5 14.Bxg7 Kxg7 15.cxd5 Ne5 16.Qb2 f6 17.Nd4 Qb6 18.Qd2 a5 19.f4 Kg8 20.e3 Nf7 21.Rac1 Rc5?

21…Nh6! and black is fine.

22.Ne6! Rxc1 23.Rxc1 Rc8 24.Rxc8+ Bxc8 25.Qd4 Qxd4 26.Nxd4 Bd7 26…Nh6! to hold white to a small edge.

27.Kf2 Kf8 28.Ke2 Ke8 29.Kd3

Black has an awful position.  His next few moves make it worse.

29…Kd8 30.Ne6+ Kc8 31.Nf8! This should have been the winning move. Robby Adamson and I were not sanguine about black’s chances.  GM Ramirez also wondered what the hell black was doing.  We were like hens in a henhouse virtually running around in our little cyber barn.



Snap on h7?

32.Ne6+? What’s this?  There is no way John is going to repeat, I told myself (and others) – he’s just gaining time on the clock.  But then:

32…Kc8 33.Nf8 Kd8 34.Ne6+? Game drawn by repetition 1/2-1/2

Go back to the diagrammed position.  You have very good tactical and positional endgame insight if you can spot the lines which gives white a big plus, which I have posted in the comments.  The solutions (multiple!) are instructive.

Take on h7?  Take on d7?  A king move?  Very tempting possibilities, and hard to work out in the USCL time limit! Scroll down to find the answer but don't cheat!

The other matchups were equally nuts and very tense for players and spectators alike.  It was only decided in the wee hours when Arizona’s Barcenilla won Q vs R against San Francisco’s Vinay Bhat. 




From the diagram, correct for white curiously enough are several different moves. The variations vividly show the power of the long-range bishop over the constricted knight in various pawn structures where white can force a king entry.

The first candidate and clearly winning move is 32. Kc4!.

32…b5+? 33. Kd4 Ke8 34. Nxd7! Kxd7 35. Bf1! b4 36. Kc4! and wins.

Tougher is 32…b6 33. a4! Ke8 34. Ne6 Nd8? 35. Nc7+ Kf7 36. Na8! and wins. Or, 34…h5 35. Bh3 Nh6 36. Ng7+ Kd8 37. Bxd7 Kxd7 38. h3! and white will win.

For those who like simpler solutions, by the way, also very strong is the simple and straightforward 32. Nxd7! Kxd7 33. Bh3+! Kc7 34. Be6 Nd8 35. Bg8 h6 36. Bh7! g5 (black is now very soft) 37. Kc4 b6 38. a3 Nb7 39. b4 axb4 40. axb4 Kd7 41. Kd4 Nd8 42. Bf5+ Kc7 43. Bg4 Nf7 44. Bh5! Nd8 45. Ke4 and white’s king walks in and wins. Very methodical and nice domination of the B versus the N.

Not correct, on the other hand, is the tempting 32. Nxh7? Ke8 35. e4 Nh6! 36. e5 Bf5+! and there no advantage for white.