Novak Djokovic
Federer's withdrawal saw Djokovic clinch the ATP World Tour Finals title for the third time in a row.Reuters

After winning his third consecutive ATP World Tour Finals title on Sunday, world number one Novak Djokovic has stated that he is at the pinnacle of his career.

The Serb won the 2014 edition of the year-end eight-man extravaganza in London by default when fellow finalist Roger Federer withdrew just hours before the much-awaited showpiece final, with a back injury.

The Swiss maestro's withdrawal saw Djokovic clinch the prestigious title for the third time in a row. The 27-year-old also ends the season as the world number one - for the third time in four years - having won his seventh Grand Slam at this year's Wimbledon and also titles at the Masters 1000 titles in Miami, Indian Wells, Rome and Paris; in addition to the Tour Finals win.

"Right now, I'm at the pinnacle in my career," Reuters quoted Djokovic as saying.

"I physically feel very fit. I'm very motivated to keep on playing on a very high level. I'm going to try to use these years in front of me to fight for the number one of the world and fight for the biggest titles."

Djokovic also revealed that winning the French Open is now one of his "biggest goals" for the 2015 season.

The Serbian superstar has won four titles at the Australian Open, two at the Wimbledon and one the US Open but triumph at the Roland Garros has so far eluded him. However, the world number one is now determined to go all the way in the 2015 edition of the French Open, which will enable him to complete his Career Slam.

"Roland Garros is and was and still will be one of the biggest goals that I have. I'll keep on trying, of course. Any Grand Slam win is another page in the history books of this sport."

Djokovic defeated Andy Murray 8-5 in a one-set exhibition match, after the Scot replaced Federer in the fixture on Sunday.