Top seed Agnieszka Radwanska had little trouble booking her spot in the semi-finals of the Pattaya Open after seeing off Thailand's Tamarine Tanasugarn 6-2, 6-3 on Friday.

The Polish teenager, who ousted second seed Svetlana Kuznetsova at the Australian Open last month, raced through the first set and had the best of several marathon rallies in the second to reach the last four for the third time in her career.

"The first five games were over very fast, it was very easy, but then she started to play," Radwanska told reporters.

"She was hard to play in the second set, she had been making mistakes, but that all stopped. It was good to be pushed."

Radwanska will meet unseeded Russian Ekaterina Bychkova, who lost the first set and battled back from 3-0 down in the decider to beat compatriot Vesna Manasieva 4-6, 7-6, 6-3.

Seventh seed Jill Craybas of the United States reached the semis after she dismissed Slovakia's Andreja Klepac 6-4, 6-4.

Craybas will face Uzbekistan's Akgul Amanmuradova, who beat Chan Yung-jan of Taiwan 6-1, 7-6.

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