Los Angeles ? There’ll be only one Williams in the WTA Championships final.

Top-seeded Serena Williams overcame her own uneven play to beat No. 3 Jennifer Capriati, 2-6, 6-4, 6-4, in the semifinals Sunday. Older sister Venus was forced out by a leg injury trailing 5-0 in the first set of her semifinal against Kim Clijsters.

Serena Williams will play Clijsters in tonight’s final of the $3 million tournament. Williams won the title a year ago in Germany when Lindsay Davenport couldn’t play because of injury.

“Hopefully, I’ll be able to play a little better in the final,” Williams said.

Venus Williams said she twisted her left ankle in a 7-5, 6-4 victory over Monica Seles on Friday night, but didn’t feel the effects until Saturday night. The official diagnosis was a lower leg strain.

“She was really injured,” Serena said. “I don’t think she should have went out there at all.”

Serena Williams needed just over two hours to put away Capriati for her 18th consecutive victory. She is 56-4 this year, with her last loss to Chanda Rubin in August in nearby Manhattan Beach.