David2009: White had until move 113 to mate. We stay with the game until move 71 (White to play)

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A slow but sure winning method (NN vs P, central P) is to build a fortress (of the 2 Ns in front of the pawn) as has already happened in the diagram. Black cannot approach the Ns and can be herded into either the a8, h8 or h1 corners. The game might continue 71 Kb4 Kb6 72. Ka4 Kc6 73. Ka5 Kc7 74. Kb5 Kb7 75 Nd5 Kc8 76 Kc6 Kd8 77 Kb7 Kd7 78 Ne3 (rebuilding the fortress) Kd8 79 Kc6 Kc8 80 Nc4 Kd8 81 Kd6 Ke8 82 Kc7 Ke7 83 Ne3 (the fortress again) Ke6 84 Kd8 etc with a mate in 24 (see kibitz to De Leon Justo vs R Camejo Almeida, 2001). This method is certainly not the fastest but is reasonably easy to remember.