French second seed Amelie Mauresmo advanced to the semi-finals of a 1.3 million-dollar WTA Hard-court Tournament here on Friday when Russian sixth seed Nadia Petrova joined a large list of injured players. Mauresmo led 4-6, 7-5, 2-0 when Petova retired with a strained right pectoral muscle, what has become a familiar injury this week.
In the semi-finals, Mauresmo will play Belgian fourth seed Justine Henin-Hardenne, who ousted Czech Nicole Vaidisova 7-5, 7-6 (7/4).
Russian top seed Maria Sharapova pulled out of the US Open tuneup last Sunday after aggravating a right pectoral strain last week in Los Angeles.
Belgian seventh seed Kim Clijsters, who needed only 40 minutes to defeat Italy's Flavia Pennetta 6-0, 6-1 in another quarter-final, advanced by walkover to the match when Serbian Ana Ivanovic pulled out with a right pectoral strain.
Pennetta had reached the quarter-finals when US fifth seed Serena Williams withdrew with left knee pain.
The limping lot left major question marks about the state of women's tennis just 10 days before the start of the final Grand Slam event of the season at Flushing Meadows.
Clijsters advanced to a Saturday semi-final against Russian Anastasia Myskina, who eliminated Argentina's Gisela Dulko 6-4, 7-5.
RESULTS (x denotes seed):
Quarter-finals: Anastasia Myskina (RUS) bt Gisela Dulko (ARG) 6-4, 7-5; Kim Clijsters (BEL x7) bt Flavia Pennetta (ITA) 6-0, 6-1; Amelie Mauresmo (FRA x2) bt Nadia Petrova (RUS x6) 4-6, 7-5, 2-0, re0tired, strained right pectoralis muscle; Justine Henin-Hardenne (BEL x4) bt Nicole Vaidisova (CZE) 7-5, 7-6 (7/4).