BEIJING (AFP) - Novak Djokovic captured his third ATP title of the year at the China Open on Sunday, outlasting giant killer Marin Cilic of Croatia in a blistering baseline battle, 6-2, 7-6 (7/4).

The Serbian second seed took advantage of a 90-minute rain delay, which came at 2-2 in the first set, coming back on centre court at the Beijing Olympics tennis venue with sharper ground strokes and well-placed serves.

The big-hitting Cilic -- who beat fourth seed Nikolay Davydenko and top seed Rafael Nadal en route to the final -- kept up a barrage of huge shots from the backcourt but Djokovic mixed up the pace to throw him off, forcing errors.

After holding serve to go up 3-2 in the first, Djokovic broke Cilic straight away and then a second time to take the set, with the 21-year-old Croatian the victim of two unlucky net cords in the final game.

In the second, Cilic -- a wild card entry here -- and the 22-year-old Serb traded breaks three times to force a tiebreak, with the Croatian failing to serve out the set twice.

Djokovic took control mid-tiebreak, winning a rally after Cilic slipped and fell to go up 4-2. The Serb closed it out on his second match point when the Croatian sent an inside-out forehand sailing wide.

Both players agreed that the light rain shower had been a factor in the outcome of the final.

"I certainly played much better after the rain delay," said Djokovic, who went home with the 500,000-dollar winner's cheque. "I kind of got my nerves together... I was very fresh on the court after that."

"Even though it was a straight set win, it wasn't easy at all. Marin could have had at least a set under his belt," the Serb said, congratulating Cilic on a great week in Beijing.

The Croatian said he had trouble adjusting to the cooler temperatures and the slower on-court conditions after the break.

"I didn't find the right range. I was a little bit struggling with that," Cilic said.

"He was defending really well and so it was tough to get some free points. I think I didn't serve well today... In the crucial moments, he played well."

Djokovic, by reaching the final, is assured of taking over the world number three ranking on October 19, surpassing injured Scot Andy Murray. He has already qualified for the season-ending championship in London in November.

Both men will head straight to Shanghai for the next leg of the ATP Tour's swing through Asia.

In the women's final, Russian sixth seed Svetlana Kuznetsova was leading Poland's Agnieszka Radwanska one set to love late Sunday.

Also on Sunday, American twins Bob and Mike Bryan won the men's doubles final, defeating Andy Roddick and doubles specialist Mark Knowles in straight sets, 6-4, 6-2, for their sixth title of the year.

China's Peng Shuai and Taiwan's Hsieh Su-wei won the women's doubles title late Saturday, beating Russia's Alla Kudryavtseva and Ekaterina Makarova, 6-3, 6-1.