Is there an engine able to solve this hard one ?

[Vinvin]

May be it requires more than 10h on a quad core ...
[d]4k1rr/1R1R3p/8/8/8/2K5/7P/8 w k - 0 1
1.Rd2!!

[Event "quiet aggressive maneuvers"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Pos 25"]
[Black "?"]
[Result "1-0"]
[SetUp "1"]
[FEN "4k1rr/1R1R3p/8/8/8/2K5/7P/8 w k - 0 1"]
[PlyCount "13"]

1. Rd2 Rf8 2. Kc2 h6 3. h3 h5 4. h4 Rhg8 5. Kb2 Rh8 6. Ra7 Rhg8 7. Ka2 1-0

[Sven]

Hi Vincent,

a nice position! Any idea why 2. Kc2, 3. h3, 4. h4 are required, i.e. why the following would not work?

1. Rd2 Rf8 2. Kb2 h6 3. Ka2 Rhg8 4. Ra7

Sorry if the answer is kind of trivial, no analysis engine available here at the moment ...

Sven

[Vinvin]

1. Rd2 Rf8 2. Kb2 h6 3. Ka2 Rhg8 4. Ra7

Because 2...Rhg8! and white have a bad timing. There's some subtle zugzwang in the position.
2.Kc2 is required !

[Sven]

Ok, now I see the point. After 1. Rd2 Rf8 2. Kb2? Rhg8! 3. Ka2 Rf4 4. Ra7 Rfg4 white is missing a tempo (can't avoid rook exchange by 5. ... Rg2), and Rxh7 will of course end up in a draw.

So indeed a nice one!

Sven