Salvaging a draw

Managed to salvage a draw from a lost middle game. I was two pawns down in the middle game. My opponent managed to promote a pawn(he chose a rook) and I had to sacrifice my knight to capture it. At this stage I was a rook veruss a pawn down! Yet I managed to get a draw. So conclusion from this game is that it is possible to hold a draw pawn versus rook! Have a look at the game for your self.