Top seed Caroline Wozniacki outfought Russia's Elena Dementieva 1-6, 6-2, 6-3 to win the Pan Pacific Open on Saturday.
Victory in the $2 million tournament means the Dane can leapfrog Serena Williams at the top of the world rankings if she reaches the quarter-finals at the China Open in Beijing next week.
"Of course being number one has always been a goal of mine but I'm just focusing on winning the next tournament," Wozniacki told reporters after winning her fifth title of 2010.
"I feel I can beat anyone now," added the 20-year-old. "I have grown a bit not only physically but mentally. It's my 11th (career) title. I'm so happy."
Seventh seed Dementieva rued missed opportunities after suffering an abrupt meltdown at the business end of the deciding set in the Tokyo sunshine.
The Russian dumped a routine forehand into the net to gift Wozniacki a break at 4-3 and never fully recovered her composure, double-faulting twice in a row to surrender the contest.
"That was not the most exciting way to finish the match," said Dementieva. "I didn't use my opportunities and let her get back in it. I allowed her to play the way she likes to."
Wozniacki pocketed $350,000 for her victory while former champion Dementieva took home $175,000.
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