31 December 2019

Finishing Things

On the last day of the decade,* it seemed appropriate to look at a rook ending that I played in my last bullet game of the year. A week ago I played a couple of bullet games, did well, and then decided I would try to get my bullet rating back above 1700. It required 160 games to achieve that feat. Along the way, I lost to a national master whose bullet rating was just under 1700. In the final game that lifted me over that milestone, I dropped a pawn early and was fighting for a draw well into the endgame.

Internet Opponent (1906) -- Stripes,J (1709) [A45]
Live Chess Chess.com, 30.12.2019

White to move

39.g5??

39.Rf7+- or Re5 or Rh7. White must protect the a-pawn to maintain the advantage.

39...Rb5= 40.g6

At first, Stockfish sees a slight advantage for White with a couple of alternatives, but as the search depth increases, the evaluation moves towards zero.

40.Rg7 Rf5+ (40...Rxa5 41.Kf2 Rc5 42.Kg3) 41.Ke1 Rxa5=;
40.Rxe4 Rxg5 41.Ra4 b6 42.axb6+ Kxb6 43.Kf2=

40...Rxa5 41.Rxe4

41.g7 Rg5 42.Kg1 a5 43.Kh2 Ka6 44.Kh3 a4 45.Rxe4 b5 46.Rg4

Black to move
Analysis Diagram
46...Rxg7 47.Rxg7 a3 48.Rg6+ Kb7 (or Ka7=; 48...Ka5 loses) 49.g3 a2 50.Rg7+ Kb6 51.Rg6+ Kb7=

41...Rg5 42.Re6

Black to move

42...b5

42...a5 43.Rd6
a) 43.e4 b6 44.e5 a4 45.Re7+ Ka6

White to move
Analysis Diagram
46.e6 (46.g7?? a3-+) 46...Rxg6 47.Ke2;
b) 43.Kf2 a4-+

43.Ke2 b4 44.Kd3 Rxg2 45.Kc4 Rg4+ 46.Kb3 a5 47.Ka4 Rg5

White to move

48.e4

48.Re7+ Kb6 49.Re6+ Kc5 50.Ra6 (50.e4 Rg3-+) 50...Kc4

White to move
Analysis Diagram
51.e4= (51.Rxa5?? Rxg6-+ 52.Rb5 Ra6+ 53.Ra5 Rxa5+ 54.Kxa5 b3-+)

48...Rg1 49.Kxa5 b3 50.Re7+

50.Ra6+ Kb7 51.Rb6+ Kc7 52.Rxb3 (52.Ka6++ Ra1+-+) 52...Rxg6=

50...Kb8

White to move

51.g7??

51.Re5= is the only move to hold the draw.

51...b2-+ 52.Re8+ Kc7

White to move

53.g8Q

53.Re7+ Kd6 54.g8Q Rxg8 55.Rb7 Ra8+ 56.Kb4 b1Q+-+

53...Rxg8 54.Rxg8 b1Q

We have reached an ending that I have attempted several times against the computer with mixed results.

55.Rg5

Black to move

55...Qxe4

55...Qe1+ is better 56.Kb5 Qe2+ 57.Ka4 Qxe4+

56.Rb5 Qa8+ 57.Kb4 Kc6 58.Rc5+ Kd6 59.Rb5 Qe4+ 60.Ka5

Black to move

60...Kc6

60...Qe2 finishes more quickly 61.Kb4 Qd3 62.Ka4 Kc6-+

61.Rb4 Qe1

61...Qd5+ 62.Ka6 Qa2+ 63.Ra4 Qxa4#

62.Ka4 Kc5 63.Rb5+

63.Rb2 is more stubborn

63...Kc4 64.Rb2 Qa1+ 0-1

Time was less critical than it might have been in bullet, as this game was played with a one second increment.



*I realize that some readers believe that the decade ends on 31 December 2020. This belief is grounded in mathematical consistency from the year 1. However, the notion of a decade is an artificial construct grounded not in mathematics but in human culture. Most people who are doing ten-year retrospectives are doing them now, not one year from now. The Western calendar has changed several times over the past two millennia. The years 1 CE and 1 BCE are rooted in speculative dating of events that more than likely took place four to seven years earlier. When the digit in the tens place advances to another number seems like the most logical time to reflect on the previous ten years, and that is what most people do.

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