He may finish the season ranked No 2 in the world, but the Serb is back to his hard-charging ways with a convincing defeat of No 1 Rafael Nadal 6-3, 6-4 in the final of the ATP World Tour Finals. With the win, Djokovic closed the gap on the head-to-head battle, which Nadal is leading 22-17. The two will finish the season having split their six matches this year, with each winning three times.