|Bridgeburner: The game is a comedy of errors and both players could consider themselves fortunate to survive this encounter in a scrappy game with blunders on both sides. |
Rubinstein plays the opening quietly, Cohn emerges from the opening with equality and could have taken the initiative on several occasions with <13...b4!>, and again <18...Bc6!> in response to <18.f4?> with a strong Queen side attack.
Rubinstein's 30.a4 was also weak and Cohn could have again taken the initiative with 30...b3! <31.Bxb3 cxb3 32.axb5 Rc1+(32...a5! is also good) 33.Kf2 R8c2+> with a strong advantage, instead of the lame 30.bxa3 which allows White to blockade the c-pawn and deny ingress to the Black Rooks.
Cohn blunders with 37...Bc4? (37...Rec5 was necessary to counter 38.Rd8). Rubinstein's 40.Rf8+?! should still win, but 40.Kf4! (threatening 41.g5+ followed by Rh8) would have been decisive:
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A. 40...Rec5 (or ...Ra5) 41.e5+ Kg7 (41...Rxe5 42.g5+ Ke7 43.Rh8 Rec5 44.Rh7+ Kd8 45.Rb8+ Rc8 46.Rh8+ followed by the exchange of all the Rooks. White's King side passed pawns win easily.) 42.Rbb8 Rf7+ 43.Kg3 Rxe5 44.Rg8+ Kf6 (44...Kf6 g5+ and mate in a few moves) 45.g5+ followed by 46.Rb7+
B. 40...Ke7 41.Rh8 Rec5 42.Rxh7+ Kd8 (42....Kf6 43.e5+ Rxe5 44.g5+ Rxg5 45.hxg5#) 43.Rb8+ Rc8 44.Rh8+ etc
C. 40...h6 41.Rg8 a5 42.Rbb8 (threatening g5+ winning the Rook) Rcc5 43.Rh8 Kg7 44.Rhd8 and Black faces major loss of material or mate.
D. 40...h5 41.g5+ Ke7 42.Rh8 Rec5 43.e5 and all the Rooks will be exchanged allowing White's g pawn to queen unimpeded.
Black's 42nd and 43rd moves are blunders but Rubinstein plays a series of inexact moves and fails to deliver the coup de grace.
Instead of 44.Rbe8, Rubinstein could have played 45.h5! For example:
44...R5c6 45.h6 Rg6 46.Rh8 Rgc6 47.Rbg8 Rg6 48.Rxh7+ Kxg8 49.Rxc7 and White will win the ending.
44...Ke6 45.Rb6+ R5c6 46.Rxc6+ Rxc6 47.Rg7 wins
44...Ke7 45.Rg7+ Kd6 (45....Ke6 46.Rb6+ R5c6 47.Rxc7 Rxb6 48.Rxc4 wins the Bishop) 46.Rd8+ Kc6 (46...Ke6 47.h6) 47.Rxc7+ Kxc7 48.Rh8 Kd6 49.Rxh7 wins
44...Be6 45.Rbe8 Ba2 46.h6 R5c6 47.g6+ Kf6 (47...hxg6 or Rxg6 48.Rgf8#) 48.Ref8+ Ke6 49.Rg7 Rc8 50.Rxc8 Rxc8 51.Rxh7 wins
With 45.Ref8+?, White dissipates most of his advantage. 45.h5! is still the best move as the King side pawn advance is decisive.
White blunders all his remaining advantage with 51.g6?. It may have been caused a miscalculation of the chances of the h pawn queening, or an exaggerated evaluation of switching the attack to the Queen wing. 51.h6 is better.
This is difficult and deeply flawed game, made fascinating by its hidden variations.