|
< Earlier Kibitzing · PAGE 2 OF 2 ·
Later Kibitzing> |
| Jul-05-16 | | nalinw: Analyzed both Rf2+ and Rxe3 to wins - and selected the latter because it seemed cleaner - didn't see the King escaping .... |
|
| Jul-05-16 | | raviarun: <Phony Benoni: Black has to be a bit careful. After <29...Rf2+ 30.Bxf2 Rxf2+ 31.R1g2 Rxg2+? 32.Rxg2 hxg3 33.Qe8+>, White has definite perpetual check chances.> Is there a chance for perpetual, after 33.Qe8+ Bf8 ? |
|
Jul-05-16
 | | Phony Benoni: <raviarun> Oh, of course not. I had better shut up now. |
|
| Jul-05-16 | | stacase: Mondayish. |
|
| Jul-05-16 | | Patriot: I saw that 29...Rf2+ was winning. But I thought 29...Rxe3 was best, not seeing a few defenses. 30.Rxe3 Rf2+ 31.Kg3 is not the defense I'm referring to - it is 31...Qf5 32.Rf3 or 32.Qh4. |
|
| Jul-05-16 | | agb2002: The material is identical.
White threatens Rxh3 and g6.
The light squares around the white king are weak. This suggests 29... Rf2+: A) 30.Bxf2 Rxf2+
A.1) 31.Kh1 Qd5+ 32.R3g2 (32.R1g3 Rxg2 33.Rxh3 -33.Qxh3 Rxg3+ wins- 33... Rxg5+ wins) 32... Rxg2 33.Qxh3 (due to 33... Rxg1+ 34.Kxg1 Qg2#) 33... Rg3+ wins. A.2) 31.R1g2 Rxg2+ 32.Rxg2 hxg2 33.Kxg2 Qf5 - + [B vs P]. A.3) 31.R3g2 Rxg2+ as in A.2.
B) 30.Kh1 Qd5+ is even better for Black than A.1.
C) 30.R1(3)g2 Rxg2+ wins a rook for a pawn without compensation. For example, 31.Rxg2 hxg2 32.g6 Rf5 33.Qh7+ Kf8 34.Bh6 Qg8 - +. |
|
| Jul-05-16 | | Cybe: Why do not 29. g6! ? |
|
| Jul-05-16 | | Prosperus: Why not 29. ... Rxe3!? 30. Rxe3 Rf2+ 31. Kh1 Qd5+ |
|
| Jul-05-16 | | Cybe: Prosperus: Why not 29. ... Rxe3!? 30. Rxe3 Rf2+ 31. Kh1 Qd5+ Because 31. Kg3. |
|
| Jul-05-16 | | AlicesKnight: I saw 29.... rf2+ 30.Bxf2 Rxf2+; and if the WK moves, 31...Qd5+ forces a R to immolate itself on the Black RP, otherwise it must do so at once; but there seems to be no 'quick death'. 26...g5 and ....h5 are attractive twin decoy sacrifices. What after 28.Rf4? - R exchange and the black Q enters the White Q-side via f5? - not clear. |
|
| Jul-05-16 | | cocker: I also went for 29 ... Rxe3 |
|
| Jul-05-16 | | WorstPlayerEver: I also got Re3 lol |
|
| Jul-05-16 | | morfishine: <29...Rf2+> and White will eventually lose a piece at <g2> ***** |
|
| Jul-05-16 | | Joseph Blackcape: 31. R1g2 and Black wins by simply taking it with the h3 pawn and staying a piece up. Then you just enforce the exchange of the remaining heavy pieces and it's an easy job. Play 32... ♕f5 and to 33. ♕e8+ you simply respond with 33... ♕f8, then if White takes on c6 instead of exchanging Queens you play ♕f4+ and White is done, as he has to either give his Queen for the Black Rook or get mated. |
|
| Jul-05-16 | | mel gibson: I saw it in seconds.
When tried on the computer it takes ages for Black to win. |
|
| Jul-05-16 | | saturn2: Black wins a piece after 29..Rf2. After having verified this I thought 29...RxB also works the same way, which is not true however. |
|
| Jul-05-16 | | dfcx: 29...Rf2+ 30. Bxf2 Rxf2+ 31.R1g2/R3g2 hxg2 wins a piece If white plays 31.Kh1 Qd5+ wins an extra rook. |
|
| Jul-05-16 | | beenthere240: Well, black began the combination with an exchange sac so really he winds up with an extra bishop, but it's still a winning advantage. |
|
| Jul-05-16 | | kevin86: Black sacrifices the exchange and regains a rook...and possibly more. |
|
| Jul-05-16 | | YouRang: Took me a moment, just because it's a rather complex position.
click for larger view
However, giving check to the enemy K always attracts one's attention, and in this case, it proves to win a piece, thanks to our Ph3, which is guarded by our Q. <29...Rf2+> Leaving white with sorrowful options: - Blocking check with a rook is no good because the pawn will take it. - Retreating the K to h1 is even worse due to ...Qd5+, and white's attack on g2 will suffice to mate. - So, white's only resort is to capture the rook with the bishop, <30.Bxf2 Rxf2>. While winning the exchange, it just leaves white in the same predicament, except now without a way to capture the rook. White *must* block with the rook, which will get eaten by the Ph3. <31.R1g2 hxg2 32.Rxg2>
click for larger view
Black is up a piece for a pawn, which should be sufficient to solve the puzzle. If white didn't resign, I'd probably continue with 32...Qf5 (defends Rf2 and attacks Pc2). My Q will take advantage of black's exposed K to win pawns and the game  . |
|
| Jul-05-16 | | drollere: i found the continuation quickly, but kept on searching because it appeared too drawish for a problem. stockfish suggests 28. ... Rf3 29. g6 as best for white in the move prior to the position. perhaps there should be a "leap year" category of problem that should only appear on february 29. |
|
Jul-05-16
 | | PawnSac: < mel gibson: I saw it in seconds. > yes agreed. It is very easy to see the winning theme, a somewhat routine tactic. < When tried on the computer it takes ages for Black to win. > The point of the CG puzzle is to find a winning position, although there are often positions that are clearly a simple and obvious win, but does require a series of moves to get to checkmate (like a K+p vs. K, or K+Q vs. K+B ending). But after reading your comment i loaded the position after ..Rf2+ 30. Bxf2 Rxf2+ 31. R1g2 Rxg2+ 32. Rxg2 hxg2 into Stockfish 7 and let it run out to.. 30/67 1:42:44 6,299,828k 1,022k -6.30
Kh2xg2 Qe6-f5 Qh5-e8+ Bg7-f8 Qe8xc6 Qf5xg5+ Kg2-f3 Qg5-f5+ Kf3-g3 Qf5xc2 Kg3-g4 Kg8-g7 Kg4-g5 Qc2-d2+ Kg5-h5 Qd2-e2+ Kh5-h4 Kg7-f7 e5-e6+ Kf7-f6 Qc6xb5 Bf8-h6 Qb5-c6 Qe2-e1+ Kh4-g4 Qe1xe6+ Qc6xe6+ Kf6xe6 d4-d5+ Ke6xd5 Kg4-f3 Bh6-d2 Kf3-e2 Bd2xc3 Ke2-d1 Bc3-g7 Kd1-c1 Kd5-e6 Kc1-c2 Here's the line added to the game for quick load and view in winboard etc. 1. e4 c5 2. Nf3 Nc6 3. Bb5 g6 4. Bxc6 dxc6 5. d3 Bg7 6. h3 Nf6 7. Nc3 Be6 8. Be3 c4 9. d4 b5 10. a3 a5 11. Ng5 Qc8 12. O-O O-O 13. f4 Rd8 14. Qf3 Bd7 15. e5 Nd5 16. g4 Nxc3 17. bxc3 f5 18. Qg3 fxg4 19. Qh4 h6 20. Ne4 Bf5 21. Ng3 gxh3 22. Kh2 Rf8 23. Rg1 Qe6 24. Nxf5 Rxf5 25. Rg4 Raf8 26. Rag1 g5 27. fxg5 h5 28. Qxh5 Rf3 29. R4g3 Rf2+ 30. Bxf2 Rxf2+ 31. R1g2 Rxg2+ 32. Rxg2 hxg2 33. Kxg2 Qf5 34. Qe8+ Bf8 35. Qxc6 Qxg5+ 36. Kf3 Qf5+ 37. Kg3 Qxc2 38. Kg4 Kg7 39. Kg5 Qd2+ 40. Kh5 Qe2+ 41. Kh4 Kf7 42. e6+ Kf6 43. Qxb5 Bh6 44. Qc6 Qe1+ 45. Kg4 Qxe6+ 46. Qxe6+ Kxe6 47. d5+ Kxd5 48. Kf3 Bd2 49. Ke2 Bxc3 50. Kd1 Bg7 51. Kc1 Ke6 52. Kc2 the position after 52.Kc2 is...
click for larger viewbut there is plenty of opportunity along the way for white to err. For example, after 33. Kxg2 Qf5 34. Qe8+ Bf8 35. Qxc6 Qxg5+ 36. Kf3 Qf5+ 37. Kg3 Qxc2 .... 
click for larger viewIf white gets greedy and tries 38.Qxb5? then Qxc3+ and Qxd4 and the C pawn queens very quickly, or if 38.Qe6+ Kg7 and white does not have Qg4+ available because of ..Qg6 forcing the queens off, followed by ..e6 and white is completely busted. So it is not difficult to see why Stockfish chooses 38.Kg4 as there is no other chance of a repetition. The point being that the final position in the game with extra piece is, with careful play, a not too difficult and almost "textbook" win for black, although, as you point out, it takes some moves to win the won position. |
|
| Jul-05-16 | | Patriot: <PawnSac> But of course! Every tactics book out there, unless they are checkmate problems, involves finding a winning combination that doesn't go on until mate. It's about attaining a winning advantage. An actual game, if the player doesn't give up, requires winning technique. |
|
| Jul-05-16 | | wtpy: Mr. Owen seems to be adding some chess notation to his word salad,perhaps as garnish. |
|
| Jul-09-16 | | andrewjsacks: Mr. Owen may be a direct descendant of James Joyce. I like his style and whey with worrrds. |
|
 |
|
< Earlier Kibitzing · PAGE 2 OF 2 ·
Later Kibitzing> |
Kibitzing
sac: 29...Rf2+