Roger Federer became the first player to win the ATP World Tour finals six times when he beat France's Jo-Wilfried Tsonga 6-3, 6-7, 6-3 in the final at the O2 on Sunday.
The 30-year-old, playing in his 100th tour final, took the first set after breaking Tsonga's serve in the eighth game and he broke again in the second before the Frenchman fought back.
Tsonga saved a match point in the tiebreak before winning it 8-6 but Swiss Federer stayed calm to break for 5-3 in the third set and serve out for victory in the season-ending tournament.