Monday, November 17, 2008

Bishops of Same Color Ending

If you actually read my post about directing at the club last Monday night, you may have picked up on the fact that I was one of the first round upset victims. If there had been an upset prize, my opponent would have won it. (647 point difference.) He had not played since April, but his dad told me he wanted to start playing again. You never know what to expect when you play a 13 year old kid who hasn't played in 6 months. You ask yourself has he spent the last 6 months playing hundreds of blitz games on ICC, and is now 1800 strength? I knew that wasn't the case. The family doesn't even have email, much less an ICC account.

Lack of Internet not withstanding, I didn't think I could take him lightly. His dad and I have had some tough games over the years. I figured he'd been doing some studying with his dad. (He had not been.) I must say I was taken aback how well he played the opening. He played the Qc2 line against my Nimzo-Indian, and rattled off his first 15 moves in about a minute. I figured sooner or later the blitz pace would catch up with him, and he'd make a mistake. However I burned a lot of time in the middle game trying to free up my position. At one point he had sac'ed a pawn to weaken my king side, and then won it back a few moves later.

Eventually we traded down to the position below:

He had just played 48. Kg4. Despite my ugly f pawns and his 3 on 2 majority on the queen side, I thought it was rather drawish at this point. I was way down on the clock, but I didn't think that would be an issue. I even offered a draw within the next few moves. I thought he might take it because of the rating difference. He decided to take on the clock difference. I didn't really see a way for him to convert the majority, and I figured we would just fiddle around with our bishops. I played 48...Bc4. My plan was to maintain control of the f1-a6 diagonal so that he can't create a passer. That move was a mistake. Even though it looks totally counter intuitive, I should have retreated my king with 48... Kg7, with the idea of bringing him back towards the queen side. A possible continuation which gives me good drawing chances is 49. Kf4 Kf8 50. Bd5 Ke7 51. Ke4 Kd6 52. Bxf7 Bxc6+.

The game continues 49. Kf4 Bd3 50. Bg4 Bb5 51. Bf3 Bc4 52.Kg4 Bb5 53. Kg3 Kg5 54. Be4 Ba4?! This was risky, but I was trying to simplify by trading some of the pawns. 55. Bd3 Bxc6 56. Bxa6 Kxf5 57. b5?! to reach the position below:

I have about 5 seconds left. I'm thinking at this point after I move the bishop he'll play 58. b6 axb6 and I can sac the bishop for the b pawn, and the game will be drawn. That's the right idea, but it's dependant on the black bishop being placed on the correct square. 57...Bd5?? I felt I needed to cover b7 with my bishop. In reality white has nothing after 57...Bd7 58. b6 cxb6 59. axb6 Bc6. Instead my bishop move gives him the crucial check will set a road block to my coverage of the queening square. 58. Bc8+! Ke5 59. a6 Kd6 60. Bb7! Now my bishop is totally cut off. I looked, but there was no defense. In the mean time those few precious seconds ticked down to zero. 1-0

Edit: I was looking at the position again after Chess Tiger had left some analysis in the comments section. I realized after looking at the position again that White messed up when he played 57. b5. Had I found the correct move of Bd7 I'm okay. However if he had switched his move order and played 57. Bc8+ first I have major problems. This is one possible continuation. 57. Bc8+ Ke5 58. a6 Bb5 59. a7 Bc6 60. b5 Ba8 61. b6 cxb6 62. Bg4 Kd4 63. Bf3 Bxf3 64. Kxf3b5 65. a8=Q b4 66. Qa7+ Kc3 67. Qc7+ Kb2 68. Ke3 Ka3 69. Kd3 f5 70. Kc2 b3+ 71.Kc3 Ka2 72. Qa5+ Kb1 73. Kxb3 f4 74. Qe1# I'm not sure either of us would have found all of this. I may have flagged along the way.

We hear a lot about bishops of opposite color endings and how drawish they tend to be. Bishops of same color seem like they should be drawish too, except that the one light squared bishop can block off the queening square from other light squared bishop. In your opposite color bishop ending the one bishop can block the pawns and the opposite colored bishop can't force that bishop away. If the king can't penetrate then you will have a draw. Below is the same position with after 57 b5. But now Black's bishop is on the dark square c5 instead of c6. Can black hold with Bd4?

Fire away! I'd be interested in seeing what my end game enthusiasts think.


chesstiger said...

Bd4 is a possibilitie, another is Bb4.

1. ... Bb4 2. Bc8+ Ke5 3. a6 Bc5
1. ... Bb4 2. b6 cxb6 3. axb6 Bd6

Polly said...

Tiger: As your lines show, white can't make any progress if black has a dark squared bishop. As long as Black does not leave the g1-a7 diagonal Black has no problems holding a draw.

While I was comparing the two positions I did some more analysis on the actual position. White misplayed it. I've added additional notes to my analysis.