Tomas Berdych rallied for a 6-7 (3/7) 7-5 7-6 (7-3) victory over Andy Roddick in the semi-finals of the Japan Open.

Berdych advances to face fifth seed Juan Martin del Potro of Argentina, who posted a 6-3 4-6 7-5 victory against fourth-seeded Richard Gasquet of France.

The world number eight, Roddick claimed his 26th career title at the China Open last week and was looking for his first set of consecutive championships since claiming three straight tournament victories at Montreal, Cincinnati and the US Open in 2003.

Berdych spoiled those hopes by rebounding to take the second set after losing the first on a tie-break. The world number 27, Berdych fell behind 3-0 in the third set but battled back to force a tie-breaker, cruising past Roddick.

Roddick fired 25 aces, but Berdych was nearly equal to the task, registering 17 to take the match in two hours 13 minutes.

Berdych, who has three career titles, will be looking for his first championship since Halle in 2007.

Del Potro has been on fire of late and is eyeing his fifth title of the season. He had never won on the ATP Tour before capturing four consecutive tournaments during the summer, and he followed that with an impressive run at the US Open into the quarter-finals.

The 20-year-old blasted 14 aces and won four of seven break points, downing Gasquet in just over two hours. It was the second win in three matches for del Potro against Gasquet.

In the women's draw, top-seeded Caroline Wozniacki advanced to the final with a 6-4 6-3 victory over Jarmila Gajdosova of Slovakia.

Wozniacki will meet fifth-seeded Kaia Kanepi in the final after the Estonian posted a 6-4 6-4 triumph over Canadian Aleksandra Wozniak in their semi-final.

The world number 16, Wozniacki is eyeing her third title this season after downing Gajdosova in 75 minutes. The 18-year-old Dane fired four aces and saved five break points to book a spot in her third final of the year after winning titles at Stockholm and New Haven.

After failing to make it past the first round in her last two tournaments, Wozniacki has turned things around here, losing only one set in four matches.

Kanepi needed nearly two hours to get past Wozniak and advance to her second career final. Ranked 33rd in the world, Kanepi was a finalist at Hasselt in 2006 and has semi-final appearances at Acapulco and Seoul this season.

The final here will be the first meeting between Kanepi and Wozniacki.