18 January 2017

Blowing the Ending

This morning on Chess.com, I beat NM Farzad Abdi in a three minute game. However, I completely blew the ending and won only because my opponent ran out of time in a dead drawn pawn ending.

Black to move

I played 55...Ra3+ and swapped rooks, which produced a pawn ending where my opponent easily seized the opposition and a dead draw. However, at this point I had 46 seconds remaining to his 11 seconds. I played against his clock and prevailed.

I was happy to get another blitz win against a titled player, but then spent a fair bit of time playing positions from earlier in the game against Stockfish 7. I learned that at three minute time controls, and even with a little more time to think, this ending is not a simple win.

55...Kf7 keeps winning chances alive.

A few moves earlier, I had an easier win.

Black to move

My 52...Rf2+, played after 4.6 seconds thought, did little to secure the win.

52...g5 advances the second pawn without allowing White's king to interfere.

A few moves earlier, I looked at and rejected the strongest move, using a mere 1.4 seconds. At the time, I had 1:03 to my opponent's 0:25.

Black to move

I played 48...h3.

Better was 48...g6+ 49.Ke4 h3 and then the feared checks lead only to 50.Ra7+ Kg8 51.Ra8+ Kg7 52.Ra7+ Kh6

Analysis Diagram
After 52...Kh6
Threatening the h-pawn with 53.Ra3 does not help White because Black has 53...Rg4+ 54.Ke5 Rh4 and with the rook behind the h-pawn, White's rook must take up a passive position on h1. Alternately, White can play 54.Kf3 and Black can exchange the rook for a new queen with 54...h2!

Going back earlier in the game, I had this position and the move.

Black to move

Play proceeded 38...Ke6 Ra7, and I thought that 39...g5 would be an error in the light of 40.Ra6+ Kxe5 41.Rxh6. My assessment was incorrect. White's king is too far away. White will be forced to give up the rook for the pawn.

After playing several other positions against the computer with mixed results, I found this one remarkably simple.

Analysis Diagram
After 41...Rxh6
41...g4 42.Rg6 Kf4 43.Rf6 Kg3 44.Kb3 Kg2 45.Kc4 g3 46.Kd3 Re8 47.Rg6 Kf2 48.Rf6+ Kg1 49.Rg6 g2 50.Rh6

Analysis Diagram
After 50.Rh6
And having reached a textbook Lucena, I built a bridge.

50...Re5 51.Rh7 Kf2 52.Rf7+ Kg3 53.Rc7 Rg5 54.Rc1 Kh2 55.Ke4 g1Q 56.Rxg1 Kxg1 and mate in fifteen.

It was nice to get the win, even from a dead drawn position. It is more important to learn how to win such positions more easily. My opponent misplayed the opening to give me an easy and comfortable middle game, but then I overlooked some of his resources in the endgame.