White to move. Is this a win or draw?
Chess Daily News from Susan Polgar
Endgame improvement
About Author
White to move. Is this a win or draw?
It looks like a draw to me. 1.b7 R56+, if the white king goes to the b-file, …Ra1 with the idea of …Rb1 to draw. If the white king goes to the seventh rank, …Ra7 draws. Otherwise Black keeps checking, with the idea of getting the rook on the b-file.
After 1.b7 … It’s a win for White after the King reaches B1 via the C file.
what about moving the king down the c file though? for example b7 ra5+ kc4 ra4+ kc3 ra3+ Kb2! now I think white wins, although it could take 30 moves
It’s similar to the famous Saavedra study. White wins by 1. b7 Ra5+ 2. Kc4 Ra4+ 3. Kc3 Ra3+ 4.Kb2!
I think after …Kc3, then
Ra3+ is met by …Kb2, and there are no more checks. The pawn queens.
This should be a win for white. Obviously, the first move must be b7 since on any king move, black can simply exchange the rook for the pawn.
1. b7
Now, on any move other than Ra5+ white will win with KxR or with b8(Q). Continuing:
1. …..Ra5
Now, what should white do? This is the critical juncture. As jMac noted in the first posted comment, the white king cannot play to the b-file in this position without allowing black to play Ra1 followed by Rb1 with either check skewering the newly born queen to her king, or covering b8 from a distance if white moves the king off of the b-file. However, that is not the end of the story, and I have played variations of this endgame more than a few times over the years:
2. Kc4!
The only winning move. Of course, Kc6 can also win, but white will have to play to c4 and transpose into this line anyway. White must remain on the c-file to prevent the rook from getting behind the pawn.
2. …..Ra4
As note after white’s first move, this is the only way to delay b8(Q).
3. Kb3
Now, white can go to the b-file since the white king can cover b1 on his next move. Here, Kc3 also wins. Now, there is nothing black can do, but play out the string:
3. …..Ra1
4. Kb2
Or Kc2, either covers the critical b1 square. The pawn cannot be prevented from queening now. The best black can do is force white to prove his knowledge of the queen vs rook endgame- always a challenge.
jMac,
White need not go the b-file so hastily, nor the 7th rank at all.
According to Averbakh it’s a win for White, even if white king will have to go all the way down to b2, through c3.
Win for white with b7, and avoid b file till rook can’t check and then promote queen.
The trick is to take the b-file with the white king on b3 to stop Rb1. White wins.
It might even be a win for black if he can bring up his king.
What after R-checks Ra3+ Kb2 and the T can’t get to the b-file, or what am I missing?
It looks like a win to me. White needs to avoid the 7th rank, and wait until he can get to b1 or b2 to stop the checks.
Let try 1.b7 Ra5+ 2.Kc4 Ra4+ 3.Kb3 should do it and a win for white
White plays b7 and wins.
Black should try Ra5+.
If white plays the king to the 7th rank black can draw with Ra7. If the king goes to the b-file black plays Ra1 with Rb1+ to follow and draw. Therefore the only way to win is:
1. b7 Ra5+ 2. Kc4! Ra4+ 3. Kc3! Ra3+ 4. Kb2! and the pawn will promote.
In this final position, the ending Q+K vs. R+K should be a win for white.
White wins
When the King arrives at c3 and is checked in a3 white plays Kb2 and wins
1. b7 and the white king can escape the checks by marching down the c file.. Kc5-c4-c3-b2
White is winning;
1.b7 Ra5+ 2.Kc4 Ra4+ 3.Kc3 Ra3+ 4. Kc2 Ra2+ 5.Kb1! And pawn promotes
1.b7 Ra5+
2.Kc6 Ra6+
3.Kc7 Ra7
4.Kc8 Rxb7
5.Kxb7
– Game DRAW 1/2-1/2
This is a theoretical win for White.
1.b7 Ra5+
2.Kc4 Ra4+
3.Kb3! Ra1
4.Kb2
And Black cannot avoid the promotion.
However, a Queen vs Rook endgame arises!
Some people call it the Devil’s Endgame, because against trick defense the winning path could be tough to find, and the winning side must be carefull to not reach the fifty moves rule.
So, the result could be a win or a draw, depending on the technique of the players, I mean in a pratical game.So the previous preparation of both sides are decisive.There are plenty of books on this subject and all of them aware the reader by the dificult of the Queen vs Rook pawnless endgame.
Best regards
Best regards
but what if the wh k plays to b2… oh oh no more chks or skewers
han
i think white is clear win