The Scot downed his Serbian rival 6-3, 6-4 to win the prestigious season-ending event for the first time in his career.

After overtaking Djokovic as world number one earlier this month, Murray knew that he had to match his achievement at the World Tour Finals in order to stay at the summit.

There was plenty riding on today's final, then, and it was the back-to-back Olympic champion who proved too strong.

Some thought that double Wimbledon champion Murray would be too fatigued for today's contest after he endured a marathon semi-final against Canada's Milos Raonic.

Djokovic, in contrast, breezed past Japan's Kei Nishikori, but it was the home favourite who took control as the Serbian was hit by unforced errors.

Murray broke in the first to make it 5-3 with a fine forehand winner, before going on to take the set.

In the second set the writing was on the wall for the defending champion, who was looking for a sixth title, as Murray opened up a double break.

Djokovic broke back once but the Scot claimed the title with his third match point to finish the season on top of the standings.

"It’s a very special day, playing against Novak in a match like this," said Murray after his win on the hard court.

"We’ve played in Grand Slam finals, Olympics and matches like this - it’s been a tough rivalry. 

"I’ve lost many of them, but I am happy to have got the win today to clinch the year-end number one. 

"It’s very special, it’s something that I never expected. 

"My team and family have been a great help, making a lot of sacrifices for me and my tennis. 

"I’d like to congratulate Novak on everything he has achieved this year."

In the men's doubles final, Finland's Henri Kontinen and Australia's John Peers beat South Africa's Raven Klaasen and American Rajeev Ram in a match tie-break.

They triumphed 2-6, 6-1, 10-8.