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Tony Gardner
Daedalian Member

Posted: Wed Sep 09, 2009 8:37 am    Post subject: 1

The following study comes from the chess page of Tim Krabbé, renowned Dutch collector of chess gems and curiosities:

White to play and win
D. Gurgenidze & V. Kalandadze, 1975

Krabbé calls it one of his favourite end game studies. A quick search on the GL using the names of the composers didn't yield any hits so my guess is it hasn't been used here yet and I thought I'd share it with you guys.

Small hint for solving: the title of Krabbe's entry dealing with this study is Pawn in Reverse
Antrax
ESL Student

 Posted: Wed Sep 09, 2009 10:20 am    Post subject: 2 I'll take the first wrong stab: e8=N? RxN or anywhere along the e column then obvious Ra1 mate, if RxR then Nd6 and unavoidable Nb7 mate. Other rook moves along the first row are answered with Nd6 and if RxN or moving to block Nb7, then Ra1 mate. What'd I miss?_________________After years of disappointment with get rich quick schemes, I know I'm gonna get rich with this scheme. And quick!
Antrax
ESL Student

 Posted: Wed Sep 09, 2009 10:23 am    Post subject: 3 Oh, I see a line I missed: ..Rg1 and if Nd6 then Rxg4+ with either endless check or forced stalemate, and if RxR then hxR=Q and I don't see a way to escape at least perpetual check (most likely an actual mate is in there somewhere). So, I guess back to the drawing board._________________After years of disappointment with get rich quick schemes, I know I'm gonna get rich with this scheme. And quick!
Nsof
Daedalian Member

 Posted: Wed Sep 09, 2009 8:24 pm    Post subject: 4 i think it will still work with 1. e8=Q Rg2 2. Kh5 so if 2...RXg4 then 3 Ra1# _________________Will sell this place for beer
Zag
Tired of his old title

 Posted: Wed Sep 09, 2009 9:36 pm    Post subject: 5 I still don't think that works, Nsof. 1. e8=Q (or N) Rg1 2. Kh5 Rf1 You could then move g5, and march the king and pawn down as he bounces between f1 and g1, and you promote yet another pawn, but it doesn't do you any good, that I can tell. if you leave the king still for a turn, the R can put him into perpetual check, and you don't have a one-move mate with a Q or a N on e8, while the black rook stays on the 1 row.Last edited by Zag on Wed Sep 09, 2009 9:45 pm; edited 1 time in total
Nsof
Daedalian Member

 Posted: Wed Sep 09, 2009 9:41 pm    Post subject: 6 missed that._________________Will sell this place for beer
Zag
Tired of his old title

 Posted: Wed Sep 09, 2009 9:47 pm    Post subject: 7 got it 1 sec
Zag
Tired of his old title

 Posted: Wed Sep 09, 2009 9:50 pm    Post subject: 8 crud. never mind I was thinking that you could start by promoting the pawn to Q, then walk the other pawn down, become a queen, then walk it back up to the 5 row. Now you have two queens attacking b5. However, if you promote to Q and not N as Antrax suggested, then RxR stops you, I think.
Jack_Ian
Big Endian

 Posted: Thu Sep 10, 2009 8:35 am    Post subject: 9 After a quick look at the puzzle, I suspect that the pawn on B2 must play an important role, since it's not needed to keep the King trapped.. It looks very interesting. I'm looking forward to examining it when I get a chance.
Zag
Tired of his old title

 Posted: Thu Sep 10, 2009 2:28 pm    Post subject: 10 Oh, I know what purpose that pawn plays. It keeps you from moving a Q to a1 without first moving into the 1 row. Without that pawn, start with Antrax's promote to knight, and his later black response of using the rook to threaten perpetual check constantly. With the black rook bouncing back and forth, walk the other pawn to become a queen, walk it back up one step, then strike on the diagonal. 1. e8=N Rg1 2. Kh5 Rf1 3. g5 Rg1 4. Kh6 Rf1 5. g6 Rg1 6. Kh7 Rf1 7. g7 Rg1 8. Kh8 Rf1 9. g8=Q Rg1 10. Qg7 Rf1 11. Qa1+ RxQ 12. RxR# but 11 is impossible with the b2 pawn.
Zag
Tired of his old title

 Posted: Thu Sep 10, 2009 2:54 pm    Post subject: 11 OK. I really have it this time. Like all good hints, it only makes sense once you no longer need it. Like before, but walk the king and queen all the way backwards to the 3 row, in the reverse of how you walked the pawn up to promote it, plus one more row. 1. e8=N Rg1 (include Antrax's reasons that this is black's only option) 2. Kh5 Rf1 3. g5 Rg1 4. Kh6 Rf1 5. g6 Rg1 6. Kh7 Rf1 7. g7 Rg1 8. Kh8 Rf1 9. g8=Q Rg1 10. Qg7 Rf1 11. Kh7 Rg1 12. Qg6 Rf1 13. Kh6 Rg1 14. Qg5 Rf1 15. Kh5 Rg1 16. Qg4 Rf1 17. Kh4 Rg1 18. Qg3 Rf1 Now, with the black pawn at h2 in the rook's way, you are safe from perpetual check by the rook. 19. Nd6 Rf4+ 20. Kh3 Rh4+ 21. Kg2 R moves anywhere 22. Ra1#
Tony Gardner
Daedalian Member

 Posted: Thu Sep 10, 2009 3:34 pm    Post subject: 12 Spot on, Zag! Krabbé includes the comment that the "unthematical" (as he calls it) 16.Qg3 is in fact one move quicker: 16. ... Rf1 17. Kh4 Rd1 (Rf4+ 18. Kh3 Rh4+ 19.Kg2 and 20. Ra1#) 18. Nd6 Rd4+ 19. Kh3 Rh4+ 20. Kg2 any 21. Ra1# Apparently, in English there is no expression for this specific situation, i.e. a rook that threatens to continuously check the king and cannot be taken due to immediate stalemate. Krabbé has termed it the 'rambling rook', in analogy to the Russian (beshenaya ladya) and Dutch (dolle toren), both literally meaning "crazy rook".
PuzzleScot
Daedalian Member

 Posted: Thu Sep 10, 2009 4:55 pm    Post subject: 13 Am I missing something? e8=N Rg1 Kh5 Rxg4! Nd6 (say) Rg5+ Kh4/6 with perpetual check from there on, with R on g and K on h.
Zag
Tired of his old title

 Posted: Thu Sep 10, 2009 5:26 pm    Post subject: 14 Yep. As soon as black's rook leaves the 1 row, he must keep white in check the whole time or he loses. e8=N Rg1 Kh5 Rxg4 Ra1#
PuzzleScot
Daedalian Member

 Posted: Thu Sep 10, 2009 7:05 pm    Post subject: 15 Just had that 'Aaaaahhh of course!' moment. Nice one. Thanks. I remember an excellent end-game puzzle where the pawn was promoted to a different piece dependant on black's move. When I say remember... anyway, this is nearly as good as that
mith
Pitbull of Truth

 Posted: Thu Sep 10, 2009 10:12 pm    Post subject: 16 Thinking of this?
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