Third seed Svetlana Kuznetsova scored a gritty 3-6, 6-3, 6-4 victory over unseeded Venus Williams on Friday to reach the semi-finals of the Warsaw Cup.

The Russian will bid to reach the final for the fourth successive year when she faces unseeded Alona Bondarenko, who advanced when fellow Ukrainian Julia Vakulenko retired with a wrist injury while trailing 6-2, 3-1.

Top seed Justine Henin defeated unseeded Italian Mara Santangelo 6-2, 6-1 and next plays fourth-seeded Serb Jelena Jankovic, who progressed when Anna Chakvetadze of Russia retired with a shoulder injury when trailing 7-6, 3-1.

Kuznetsova was outplayed in the opening set as an aggressive Williams hit a succession of sizzling groundstrokes.

It was difficult for Williams to maintain such a high standard and Kuznetsova's determination to battle for every ball helped her level matters.

Williams, who stayed in contention despite hitting nine double-faults, broke for a 4-2 lead in the deciding set before the esilient Russian reeled off four games in a row.

"I was fighting a lot and I think that was the key today," Kuznetsova told reporters.

"In the second set I told myself it's a new set and I was going to have chances and to keep fighting."

Henin gave up only five points on serve in the first set as she took control against Santangelo

The Belgian then effectively ended the match by taking a 3-0 lead in the second.

"Today was almost perfect," said Henin. "It was a good match.

"I'm very happy the way I played, very consistently and very focused on every point."

Jankovic and Chakvetadze were evenly matched until the Russian's challenge collapsed when she lost the first-set tiebreak 7-1.

"I thought she had something wrong in the tiebreak," said Jankovic.

"We were both on the same level and all of a sudden she kind of gave up and she wasn't the same player."

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