Seems counter-intuitive. There doesn't seem to be much against the more obvious 14...Bg6.

Might not have been such a bad idea, though. White's is a "good" bishop - quite mobile even though there are a lot of pawns about. Although its hard to see the rooks coming off any time soon, White might have to think twice about such an exchange, later, as the knight might well come into its own with a vengeance in a Q+N vs Q+B endgame.

Black might have been better to have recaptured with the Q on move 33. However, he is by no means out of the game at this point. For instance, 35...Nc5 36.Qf3 Rd7 37.Rd1 Nxd3 38.Rxd3 Rxd3 39.Qxd3 Qxa5 is a level endgame. Avoiding these exchanges doesn't give White much joy, as Black's rook would then penetrate to the 7th rank.

Black might have tried grabbing the a-pawn whilst the grabbing was good, i.e. after 37.Rd1!? White gets a bit of an attack, but it seems indecisive: 37...Qxa5 38.Qc8+ Ne8 39.Bc4 Qa4! 40.Qd8 Qc2+ 41.Rd2 Qe4+ and Black is OK.

A very good spot for the Q, as Black is reduced to near passivity. But these Q+P endings are very difficult to win, even with an extra pawn, without you have a passed pawn somewhere, or the means of creating one soon. Black's drawing chances from here aren't too bad...