Novak Djokovic has gone top of Group B in the ATP World Tour Finals after beating Roger Federer at the O2 Arena in London this evening.
The Serb beat the Swiss 6-4 6-7 6-2 after surging past his opponent with a scintillating display in the third.
Federer looked to have been sapped of his energy following a successful tie-break in the second. He eventually won it 2-6 to take it to the third, but he was no match for Djokovic in the following set.
The world number two eased past Federer in the third to secure his first win of the tournament.
