Djokovic win 2nd tour finals title

The Serbian star, who ends a second consecutive year at the top of rankings, dug deep to break the fierce resistance of the six-time champion securing 7-6(6), 7-5 win.

"It's very satisfying for my team and myself to conclude this fantastic season with a World Tour Finals win," said Djokovic on the ATP website. "I was playing really great tennis throughout the whole week. So I cannot be more thrilled than I'm feeling now."

The Swiss took the 3-0 lead in the first set but Djokovic managed to turn the tide and prevail on a tie-break, RIA Novosti reports.

In the second set, Federer broke early again and had two set balls before Djokovic surged back, winning three games in a row.

"Today we had times where we had longer rallies, we had times where we had shorter rallies," Federer was quoted by the ATP website.

"It was good playing such points. I shouldn't have been broken as often as I was broken today. But then again, that obviously has something to do with Novak, as well. It was extremely close today."

Federer, 31, still takes home fond memories of a tournament where he eclipsed Czech legend Ivan Lendl's record of 39 wins at the Tour Finals, eventually reaching the 42 mark.

Djokovic's first triumph at the season-ending event came in 2008, when he defeated Russia's Nikolay Davydenko in a two-set final.