This was an exceptionally tricky endgame, even before it reduced to 7-men in the position shown here, which arose after Black's 60th move.
Each phase of the ending deserves careful study, starting with the position after the time control. White had a long think then but played the suspect 41 h3 whereas the online engine preferred White with 41 f5. In the next phase Black seemed to improve his position but at a critical moment he allowed the White king to attack his h-pawn and set up a dangerous passed pawn on that file.
The diagram position after 61 h4-h5, at the start of the 7-man ending, shows a very critical situation for Black (the higher-rated player and FM). He failed to see either that it was possible to prevent the White pawn queening, or that there were ways to save the game by precise play after promotion.
Only two moves hold here. The ideas that could have saved the half-point were that Black must either threaten the bishop with check at move 62 or else set up a blockade with a N on f7. The various methods of saving the ending are equally worth study: preventing the promotion, the defence with both knights, and the defence with a single knight. Black, in the game, fell into an inferior version of the latter, but an improved form of it was possible.
Alistair Hill (2159) - James P. Jackson (2343)
Generated with ChessBase 10
Download CBLight for free here