[Event "Zuerich"] [Site "Zuerich"] [Round "0"] [White "Euwe"] [Black "Averbakh"] [Result "0-1"] [FEN "r5nk/4nrpp/1q2b3/3p1pQN/p1pPP3/PpP2P2/1B2R1PP/RB4K1 w - - 0 24"] {Black has a Queenside majority, while White has a central majority. Black's protected passed pawn at b3 can be a strong asste, but for the time being it is securely blockaded. White's central pawn position is, on the other hand, in a dynamic state and hence White currently holds the initiative} 24. exf5 { This move nad White's next are not merely unmotivated exchanges, for White must find a way to free his Queensidepieces} 24... Bxf5 25. Bxf5 Nxf5 26. Rae1 {Controls the open e-file} (26. Re5 {avoiding the exchange of Queens and playing for attack instead, might have been the best idea.}) 26... Qd8 { Forcing the exchange} 27. Qxd8 (27. Qd2 Qh4 28. Nf4 Nxd4) 27... Rxd8 28. Re8 $2 {This leads to the exchange of all Rooks, after whch Black suddenly finds himself better off} (28. Re6 { White is able to attack the enemy pawns from behind}) 28... Rxe8 29. Rxe8 Re7 $1 {This move had been overlooked by White in his previous calculations. He must now permit the exchange of his other Rook, for otherwise Black will play . .. Re2} 30. Rxe7 Ngxe7 31. Kf2 Kg8 32. g4 Nd6 33. Ke3 Nb5 {One Black Knight has taken up an ideal post, and it is becoming clear that in this minor piece ending Black's protected passed pawn is a formidable factor} 34. f4 $2 { Understandably striving to advance his Kingside majority as rapidly as possible, but creating an incurable weakness at e4, which in turn enables his opponent to strengthen his gamedecisively} (34. Nf4 -- 35. Ne2) 34... Nc8 35. f5 Ncd6 36. Nf4 Nxa3 $1 { Thus Black creates a pair of united passed pawns on the extreme Queen's flank} 37. Bxa3 Nb5 38. Bc1 Nxc3 39. Ne2 (39. Kd2 Nb1+ 40. Kd1 a3 $19) 39... Nb1 0-1