Quote:
Originally Posted by DaMaGor
Wow. I didn't realize I was that close to the edge.
Yeah, now you know why I kept declining those draw offers :-)
I'd seen the general idea before (defend pawn from the side, ladder the king up, deliver a rook check to displace the king, bring the king back to advance the pawn) and sort of assumed that this endgame would be winning for me, when entering it via the bishop trade--there was nothing better, so I didn't try to analyze too deeply.
But I hadn't actually worked out all of the details, and some of the rules of thumb I had in mind were wrong--for example
1.Re2? is a draw--despite earning
three files of separation because, as DaMaGor notes, the Black king controls enough key squares to prevent the White rook from protecting the pawn from the side, and White doesn't have enough space on the left.
The only way to make progress is with 1.Rh2 and to lose a move with sidechecks, to reach:
Now, e.g., 1.Kc7 Rb3 2.Re2+ works as
is lost for Black whereas with Black to move, 1...Kf5! would draw.
The b-pawn hurts White
is a win after 1.Kc5...
Quote:
I do have a book called "Secrets of Rook Endings" by John Nunn, which is actually just an exhaustive study of R + P vs R, but in accordance with the rules, I didn't refer to it since it depends heavily on tablebases.
For the record, I think using the book would have been fine, as long as one doesn't open up the tablebases directly. Perhaps Noir_Desir can clarify.
Last edited by Sholar; 09-28-2013 at 10:07 AM.