Maria Sharapova of Russia beat two-time champion Belgium's Kim Clijsters 6-4, 6-4 at the WTA Championships on Wednesday, moving a step closer to a spot in the semifinals.

In other matches, Svetlana Kuznetsova defeated fellow Russian Elena Dementieva 7-5, 6-3, and two-time winner Martina Hingis of Switzerland pulled out a 6-4, 3-6, 6-3 victory over Russian Nadia Petrova.

Hingis' victory means top-ranked Frenchwoman Amelie Mauresmo will not finish the year as the No. 1 player in the world. That distinction will go to Sharapova or Justine Henin-Hardenne of Belgium, depending on how they fare in this tournament.

Sharapova is 2-0 in the round-robin portion, Kuznetsova is 1-0 and Clijsters is 0-1. Also in the Red Group, the seventh-ranked Dementieva is 0-2, including Tuesday's loss to Sharapova, and has little chance of reaching the semifinals for the first time since 2000.

Kuznetsova can guarantee herself and Sharapova a place in the semifinals by beating Clijsters on Thursday.

In the Yellow Group, Hingis and Petrova are 1-1. Henin-Hardenne is 1-0, while Mauresmo is 0-1.

Sharapova, the U.S. Open champion, kept Clijsters deep behind the baseline and on the run throughout, hitting crosscourt winners from both sides.

``I think the quality of my tennis today was quite high,'' Sharapova said after her 10th straight win. ``I know that I've played a lot of matches and I feel good about my game.''

After the 19-year-old Russian saved three break points in the fourth game of the second set, she took away the momentum from Clijsters and broke the frustrated Belgian in the next game.

Sharapova broke Clijsters again in the seventh game, but failed to hold for the first time in the match as Clijsters closed to 5-4.

Sharapova saved a double-break point in the 10th before her fifth ace clinched the win.

``I felt like I was moving really well and no matter how big and deep her shots were I still felt like I was in position for them. And that just comes from playing a lot of matches,'' Sharapova said.

The fourth-ranked Kuznetsova capitalized on Dementieva's erratic serve. Dementieva broke when trailing 5-3 before holding serve for the first time in four games. But Kuznetsova held and broke Dementieva for the third time to take the first set.

``I had a lot of chances that I didn't close out in the first set,'' Kuznetsova said. ``I was losing my concentration, but that's normal after a long season.''

Kuznetsova took control of the second set, breaking Dementieva with a forehand winner for a 2-0 lead. She held serve _ saving four break points _ and the match went to serve until a netted backhand by Dementieva sealed it.

``I'm looking forward to raising my game tomorrow, but today it was enough,'' Kuznetsova said.

Hingis stormed to a 4-1 lead in the first set against the fifth-ranked Petrova, who beat Mauresmo on Tuesday. Petrova broke Hingis twice en route to winning the second set.

But 41 unforced errors cost the Russian. In the deciding set, Hingis broke in the sixth game and sealed the win with a forehand pass on her second match point.

``I wanted to come out here and at least win one after yesterday's loss, so I'm very happy,'' Hingis said.

© The Canadian Press, 2007