Fundamentals (part 43)

Spanton (1923) - Jiri Navratil (2056)
Olomouc Open 2016

Black has just captured on d5 - who stands better?

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The position is dead-level, according to Stockfish11, but Komodo11.01 reckons White is half-a-pawn better. It does seem that correct plays leads to a draw, but Black has to be careful about White's queenside pawn-majority.
35.Kd3 e5 36.c4+ Kd6 37.fxe5+ Kxe5 38.b4
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38...f6?
I expected 38...f5 when 39.gxf5 gxf5 40.Ke3 g6 (other moves also draw) 41.c5 bxc5 42.bxc5 Kd5 43.Kf4 Kxc5 44.Kg5 Kd5 45.h5 is a draw. But the engines point out Black even draws by retreating his king, eg 38...Ke6 39.Ke4 Kd6 40.Kd6 Ke6 41.c5 Kd7! 42.cxb6 Kc6 43.b7 Kxb7 44.Kc5 Kc7 45.b5 f6 46.Kd5 Kb6 47.Ke6 Kxb5 48.Kf7 f5 49.gxf5 gxf5 when both players queen their last remaining pawn.
39.Ke3 Ke6
Also losing is 39...f5 40.gxf5 gxf5 41.h5 etc (40.h5 in the previous note is only a draw after 40...f4, whereas here 41...f4+ is effectively met by 42.Kf3).
40.Kf4 Kd6 41.h5 f5
There is nothing better.
42.hxg6 fxg4 43.Kxg4 Ke5 44.c5 bxc5 45.bxc5 1-0