Novak Djokovic of Serbia celebrates with the trophy after winning the men's single's final against Roger Federer of Switzerland at the ATP World Tour Finals at the O2 Arena in London Adriano Barcelona Jersey , Britain, Nov. 22, 2015. Djokovic won 2-0. (XinhuaHan Yan) Novak Djokovic of Serbia celebrates with the trophy after winning the men's single's final against Roger Federer of Switzerland at the ATP World Tour Finals at the O2 Arena in London, Britain, Nov. 22, 2015. Djokovic won 2-0. (XinhuaHan Yan) Novak Djokovic of Serbia celebrates after winning the men's single's final against Roger Federer of Switzerland at the ATP World Tour Finals at the O2 Arena in London Adrian Ortola Barcelona Jersey , Britain, Nov. 22, 2015. Djokovic won 2-0. (XinhuaHan Yan) Novak Djokovic of Serbia returns a ball during the men's single's final against Roger Federer of Switzerland at the ATP World Tour Finals at the O2 Arena in London, Britain, Nov. 22, 2015. Djokovic won 2-0. (XinhuaHan Yan) Novak Djokovic (L) of Serbia and Roger Federer of Switzerland pose ahead of the men's single's final at the ATP World Tour Finals at the O2 Arena in London Xavi Hernandez Jersey , Britain, Nov. 22, 2015. Djokovic won 2-0. (XinhuaHan Yan) Novak Djokovic (2nd R) of Serbia distributes chocolate to journalists after a press conference at the ATP World Tour Finals at the O2 Arena in London, Britain, Nov. 22, 2015. Djokovic won 2-0. (XinhuaHan Yan) Roger Federer of Switzerland holds the silver plate during the awarding ceremony for the men's singles final against Novak Djokovic of Serbia at the ATP World Tour Finals at the O2 Arena in London Thomas Vermaelen Jersey , Britain, Nov. 22, 2015. Federer lost 0-2. (XinhuaHan Yan) LONDON, Nov. 22 (Xinhua) -- World No. 1 Novak Djokovic capped a perfect season as he beat six-time champion Roger Federer to win a record fourth straight ATP World Tour Finals title at London's O2 Arena on Sunday.
The 28-year-old Serb, who lost to Federer in the group stage, broke the Swiss three times to win 6-3 Sergio Busquets Jersey , 6-4 in just 80 minutes, levelling their record with the 17-time Grand Slam winner at 22-22.
It was Djokovic's 11th title of the season, including three Grand Slam trophies. He played 88 matches in the season and won 82 of them.