World number four Svetlana Kuznetsova got off to a winning start in the WTA Championships Wednesday with a 7-5 6-3 victory over fellow Russian Elena Dementieva in the round robin stage.

Dementieva is now almost certain to exit the tournament after losing to the in-form Maria Sharapova in her opening match on Tuesday.

"I couldn't play my best here...but I've really enjoyed being here," said the 25-year-old, who is now bottom of the red group having failed to win a set in either of her two matches.

Both players struggled on their own serves in the first set, exchanging two breaks apiece, but Kuznetsova finally gained the edge by cracking the Dementieva service in the 12th to take the set 7-5.

Kuznetsova, who is three places higher in the rankings than her compatriot, continued to make the running in the second set, breaking in the second game on her way to a 4-1 lead and then serving out to take the match.

"I should have shut the match out earlier as I had a lot of chances," she said. "I lost concentration a little at times, but I'm looking forward to improving my game for the next matches."

Sharapova, who along with Justine Henin-Hardenne and Amelie Mauresmo is bidding to wrap up the end-of-year number one spot, will have the chance to take another stride towards the semis when she plays Clijsters later on Wednesday.

Martina Hingis, who won the Championships in 1998 and 2000, will be looking to bounce back from her opening day defeat to Henin-Hardenne when she meets Nadia Petrova.

The Russian was a straight sets winner over world number one and 2005 champion Mauresmo who looked rusty after returning to action following a 10-day lay-off with a shoulder injury.