I think you misjudged the position of White's king, as 41...Bc4 is not check.
Magnus Carlsen, Nanjing 2009

damn, Carlsen played good in the end game, i mean, i woudve lost if my opponent had a rook and i didnt... i just fail when it comes to moving a knight strategically
Carlsen has so far won 4 games in the first half of the 10 rounds match. In the sixth game Carlsen with leko came out a draw. Here the game. My question is what do you think of the 41st move ? why Nf5 why not Bc4+(mistake here is does not give check) winning the rook ?