Djokovic defeats Nadal

Novak Djokovic sent a strong message to Rafael Nadal and all his rivals with a convincing victory over the world number one to retain his Barclays ATP World Tour Finals title.

After losing the US Open final to Nadal, Djokovic has won 22 straight matches and used the indoor conditions to his advantage to win 6-3 6-4.

The three-time defending Australian Open champion will now head into 2014 halfway to bettering his incredible 43-match unbeaten run in 2011.

Nadal lost his only other final at London's O2 Arena to Roger Federer three years ago, and it remains the one major title he has not yet won.