London, England

Top seed Novak Djokovic of Serbia defeated second seed and six-time champion Roger Federer of Switzerland, 7-6(6), 7-5, Monday to capture his second Barclays ATP World Tour Finals trophy before 17,800 spectators at The O2.

The top-ranked Djokovic needed two hours and 15 minutes to beat Federer for his sixth title of the season, earning $1,760,000 in the process. Federer, the world No. 2, received $800,000 for his efforts.

It was a sorry loss for Federer, who was eyeing a seventh title in the season-ending event, as he led the first set by 3-0 before Djokovic regrouped and forced a tiebreak.

Djokovic raced to a 2-0 lead in the tiebreak but Federer came within 5-6 before missing a backhand that gave the Serbian the first set after a grueling 72-minute battle.

Just like the first set, Federer opened with a 2-0 lead as Djokovic committed five unforced errors.

Djokovic kept up with Federer until the Swiss tennis superstar made four straight errors, allowing him to tie at 5-5.

In the final game, Federer committed his 19th unforced error of the set to give Djokovic championship point. In the ensuing play, Djokovic hit a forehand down the line to end the match.

Meanwhile, sixth seeds Marcel Granollers and Marc Lopez became the second Spanish team to win the season-ending championships when they defeated fifth-seeded Indians Mahesh Bhupathi and Rohan Bopanna, 7-5, 3-6, 10-3.

"We finished here winning the title, so it's incredible for us," said Granollers. "We try to play as best as we can always. I think we have very good relationship. So, I think, that's one of the key of our success.

The only other Spanish duo to win the championship was Juan Gisbert Sr. and Manuel Orantes in 1975 at Stockholm, capturing the title with the best round-robin record.