Novak Djokovic finished the best season of his life in fitting style as he beat Roger Federer 6-3 6-4 to win the ATP Tour Finals title in London for a record fourth successive year.
Djokovic, the world number one tennis player, is the first player in the tournament's 46-year history to take home the trophy four years in a row.
The Serb also joins past legends Pete Sampras and Ivan Lendl on five victories at the season-ending event.
Only Federer, with six Tour Finals crowns, has won the tournament more times.
The 11th title of Djokovic's astonishingly dominant campaign served as the perfect finale to arguably the best run by any male player in the Open Era.
Playing in a record 15th consecutive tour-level final, Djokovic delivered another masterclass to record his 82nd victory from 88 matches this year and bank the winners' cheque for more than $1.5 million.
"I'm very proud, together with my team, for the achievements of the season. It could not have been a better finish. It's been a long season, but the best of my life," said Djokovic.
In dispatching Federer with such ease after an equally imperious semi-final win over Rafael Nadal, Djokovic showed why he has been able to move so far ahead of his rivals in a year in which he also won Wimbledon and the Australian and US Opens.
Meanwhile, Federer's defeat means Andy Murray is guaranteed to finish second in the year-end world rankings for the first time.
"I tried my best, I thought I played some great tennis all week and in the final, but Novak deserves the win today like so many times this year," said 34-year-old Federer.
Djokovic and Federer have been the gold standard at the Tour Finals for over a decade, lifting the trophy 10 times between them in the last 12 years and making it to the final a combined 15 times.