another endgame trade position

[jdart]

Here is another interesting one:

[d] 8/8/P3R3/r3n3/2P5/1P6/1K5k/8 w - - 0 1

In the game Rxe5 was played and White won rapidly. I think this is the best move. In the resulting endgame after Rxe5 Rxe5:

[d] 8/8/P7/4r3/2P5/1P6/1K5k/8 w - -

the 3 connected pawns are worth more than a whole Rook. But my latest build of Arasan won't play Rxe5 even at long time controls. Not sure right now if it is an eval or search issue, or both.


--Jon

[bob]

I would not worry about it. White is winning and there are several ways to pull this off, from the simple b4 to your sac.

[swami]

Bright @ Q6600

New game
8/8/P3R3/r3n3/2P5/1P6/1K5k/8 w - - 0 1

Analysis by bright-0.3a:

1.Rf6
+- (2.02) Depth: 1/3 00:00:00
1.Kc3 Kg3 2.b4
+- (2.65) Depth: 3/5 00:00:00
1.Kc3 Kg3 2.b4
+- (2.65) Depth: 3/5 00:00:00
1.Kc3 Kg3 2.b4
+- (2.65) Depth: 3/6 00:00:00
1.b4 Nd3+ 2.Kb3 Nc1+ 3.Kc2
+- (2.97) Depth: 3/11 00:00:00
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Nc5+ 4.Kb2
+- (3.42) Depth: 4/13 00:00:00
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Kg2 4.Re7
+- (3.38) Depth: 5/13 00:00:00
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Kg2 4.Re7
+- (3.38) Depth: 6/13 00:00:00 10kN
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Kg2 4.Re3 Nc5+ 5.Kb4
+- (3.42) Depth: 7/15 00:00:00 19kN
1.b4 Nd3+ 2.Kb3 Ra1 3.Rd6 Kg2 4.b5 Nc5+ 5.Kb4 Nxa6+ 6.bxa6 Kf3 7.c5
+- (3.44) Depth: 8/17 00:00:00 42kN
1.b4 Nd3+ 2.Kb3 Ra1 3.Rd6 Kg2 4.b5 Nc5+ 5.Kb4 Nxa6+ 6.bxa6 Kf3 7.c5
+- (3.44) Depth: 10/19 00:00:00 178kN
1.b4 Nd3+ 2.Kb3 Ra1 3.Rd6 Kg2 4.c5 Nxc5+ 5.bxc5 Kf3 6.Kc4 Ke4 7.Re6+ Kf4
+- (3.52) Depth: 10/19 00:00:00 231kN
1.b4 Nd3+ 2.Kb3 Ra1 3.Rd6 Kg2 4.c5 Nxc5+ 5.bxc5 Kf3 6.Kc4 Ke4 7.Re6+ Kf4
+- (3.52) Depth: 11/20 00:00:00 351kN
1.b4 Nd3+ 2.Kb3 Ra1 3.Rf6 Kh3 4.b5 Kg4 5.Rd6 Nc5+ 6.Kb4 Nxa6+ 7.bxa6 Kf4 8.c5
+- (3.36) Depth: 12/24 00:00:00 1006kN
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Nc5+ 4.Kb2 Ra4 5.Rg6 Nxa6 6.bxa6 Rxc4 7.a7 Ra4 8.Rg7 Kh3 9.Kc3
+- (3.50) Depth: 13/27 00:00:00 3343kN
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Nc5+ 4.Kb2 Ra4 5.Rg6 Nxa6 6.bxa6 Rxc4 7.a7 Ra4 8.Rg7 Kh3 9.Kc3
+- (3.50) Depth: 14/29 00:00:00 4496kN
1.b4 Nd3+ 2.Kb3 Ra1 3.b5 Nc5+ 4.Kb2 Ra4 5.Rg6 Nxa6 6.bxa6 Rxc4 7.a7 Ra4 8.Rg7 Kh3 9.Kc3 Kh4 10.Kd3
+- (3.54) Depth: 15/33 00:00:01 7946kN
1.b4 Nd3+ 2.Kb3 Ra1 3.c5 Kg3 4.Re3+ Kf4 5.Rxd3 Rxa6 6.b5 Ra1 7.c6 Rc1 8.Rc3 Rb1+ 9.Ka4 Ke5 10.c7
+- (3.84) Depth: 16/34 00:00:06 39829kN
1.b4 Nd3+ 2.Kb3 Ra1 3.c5 Kg3 4.Re3+ Kf4 5.Rxd3 Rxa6 6.b5 Ra5 7.Kb4 Ra1 8.c6 Rc1 9.Rc3 Rb1+ 10.Kc5 Kf5
+- (4.08) Depth: 17/35 00:00:08 51961kN
1.b4 Nd3+ 2.Kb3 Ra1 3.c5 Kg3 4.Re3+ Kf4 5.Rxd3 Rxa6 6.b5 Ra5 7.Kb4 Ra2 8.c6 Rc2 9.Rc3 Rb2+ 10.Ka5 Ra2+ 11.Kb6 Rb2
+- (4.11) Depth: 18/40 00:00:12 79415kN
1.b4 Nd3+ 2.Kb3 Ra1 3.c5 Kg2 4.Rd6 Nf2 5.b5 Ne4 6.Rd5 Nxc5+ 7.Rxc5 Kf3 8.Re5 Kf4 9.Re7 Kf5 10.Kc4 Kf6 11.Rh7
+- (4.50) Depth: 19/43 00:00:38 258mN
1.b4 Nd3+ 2.Kb3 Ra1 3.c5 Kg2 4.Rd6 Nf2 5.b5 Ne4 6.Rd5 Rb1+ 7.Kc4 Rc1+ 8.Kd4 Nc3 9.Rg5+ Kf3 10.b6 Nb5+ 11.Kd3 Kf4 12.b7 Rd1+ 13.Kc4 Na3+ 14.Kc3
+- (4.38) Depth: 20/43 00:00:57 384mN
1.Rxe5 Rxe5 2.b4 Re2+ 3.Kb3 Re3+ 4.Ka4 Re8 5.b5 Ra8 6.Ka5 Kg3 7.b6 Kf4 8.b7 Rb8 9.c5 Ke3 10.a7 Rxb7 11.a8Q Rb2 12.Qe8+ Kd3
+- (6.21) Depth: 20/44 00:01:11 494mN
1.Rxe5 Rxe5 2.b4 Re7 3.b5 Ra7 4.Kb3 Kg3 5.c5 Kg4 6.b6 Rxa6 7.b7 Ra1 8.Kb2 Rg1 9.b8Q Kf5 10.c6 Ke6 11.c7 Rg2+ 12.Kc3
+- (6.79) Depth: 21/44 00:01:24 603mN

(, 03.06.2008)

[swami]

I would not worry about it. White is winning and there are several ways to pull this off, from the simple b4 to your sac.

Sure. But You'd have to choose the easiest shortcut to finish the game in style