The Russian will play Serbia's Jelena Jankovic in the final after the seventh seed overpowered China's Li Na 6-4, 6-3 in the day's first semifinal at the $2 million Tokyo event.

Sharapova, 25th in the world and chasing her first title since shoulder surgery last October, took the first set with a backhand bomb off a weak Radwanska second serve.

The Russian lost her way in the second, double-faulting to hand Radwanska a 5-2 lead, the 11th seed quickly closing out the set with a huge serve down the centre line.

Sharapova had to dig herself out of a hole at 0-2 in the decider as she summoned the experience that brought her three grand slam titles between 2004 and 2008.
Shrieking louder and louder as the ferocity of her groundstrokes increased, Sharapova forged ahead 5-3 by smashing a forehand down the line, celebrating with a fist pump and a yell of "Come on!"

The 2005 Tokyo champion squandered two match points on her serve in the next game but sealed victory at the fourth attempt by ripping a blistering backhand return cross court.

Tsonga recovers

Top seed and holder Jo-Wilfried Tsonga advanced to the semifinals of the Thailand Open after a testing 6-7, 6-3, 6-4 win over unseeded Swiss Marco Chiudinelli on Friday.

The French world number seven recovered after losing a first-set tiebreak to plot his course for the semis, where he will meet Viktor Troicki or John Isner.

Second seed Gilles Simon advanced in the $608,500 tournament after fighting the pain barrier to record a 4-6, 6-3, 6-4 victory over hard-hitting Russian Evgeny Korolev.