Rafael Nadal may have ended the year ranked No.1 but Novak Djokovic demonstrated last night that the title is only on a timeshare holiday after outhinking and outplaying the Spaniard to win the Barclays ATP World Tour Finals for the second successive year and the third time overall.

Having lost top spot when Nadal defeated him to win the US Open title in September, Djokovic made it 22 straight wins as he romped to a 6-3, 6-4 victory with a performance that will send a shudder through his rivals, the Wimbledon champion Andy Murray included.

"This is a great way to finish the year," a jubilant Djokovic said, before thanking his support team including his long-time coach Marion Vajda.

Though Nadal fought to the end in typical fashion, it was a display of awesome authority from Djokovic, who crowned his return to form in the past two months with another big title.

In their 39th meeting, everything was near-perfect; from his fast start to his brilliant defence, incredible movement around the court and smart attacking all of smothered Nadal's response.

The French Open and US Open champion had beaten Roger Federer on his way to a second final but on an indoor court, against a Djokovic on this kind of form, Nadal is always fighting an uphill battle.

Right from the start, Djokovic was bristling, brooding, oozing confidence. A break of serve put him 3-0 but Nadal dug his claws in to get back on terms for 3-3. Djokovic held for 4-3 and one brilliant rally from the Serb gave him another break and he served out calmly for the opening set.

Where Nadal had troubled Federer with his swinging serve to the Swiss's backhand, Djokovic laid into the return of serve, attacking at will and dictating play.

Stretched at every turn, Nadal was forced into using the slice more on his backhand but it was powerless against Djokovic's relentlessly clean ball striking.

Another break gave Djokovic a 2-1 lead in the second and though Nadal, his every winner backed up by a "vamos" of encouragement, continued to fight, his hopes never looked more than slim.

Djokovic maintained his lead to 5-3 and then had a match point on the Nadal serve only for the Spaniard to save it with a fine serve of his own.

Serving for the match, Nadal ripped a forehand pass crosscourt and then put away a simple volley to get back to 30-30.

Djokovic, the champion in Australia, runner-up to Murray at Wimbledon and again to Nadal at the US Open, forced a second match point with a service winner but Nadal saved it with a brilliant flicked backhand pass.

An ace from Djokovic, his sixth of the match, set up a third Championship point and more great defence resulted in Nadal overcooking a forehand into the tramlines to give Djokovic victory.

It was his fourth title since losing to Nadal in New York, a loss that made him take stock of his game, step up his training regime and refocus on his the psychological aspect of his game.

The spur of another Davis Cup final kept him going but he wanted to win in London and Nadal, like all four of his other opponents this week, proved unable to stop him.

For Nadal, it was a slightly disappointing end to what has been an incredible comeback year, winning 10 titles and two more grand slams after a seven-month absence through injury.

Nadal will take a lead of around 950 points into 2014 but though Djokovic has the Australian Open title to defend in January, after that the pressure will be on the Spaniard to defend his efforts this year.

"It has been no doubt the most emotional season of my career after a tough injury," Nadal said. "It's probably one of the best seasons of my career. Even if I didn't have a chance to win today because I played against a player who played much better than me today."

There was a surprise in the doubles final as Bob and Mike Bryan, the winners of 11 titles in a brilliant 2014, were beaten 7-5, 6-7, 10-7 by the Spanish pairing of David Marrero and Fernando Verdasco.