World number one Lorena Ochoa birdied five of her last seven holes on Saturday to seize a share of the third-round lead with Sophie Gustafson in the LPGA Challenge.
Mexico's Ochoa carded a seven-under par 65 and Sweden's Gustafson shot a 66 for a 16-under total of 200.
They were six shots in front of American Angela Stanford and South Korean Sun Young Yoo, who both shot 69 for 206.
It was a further shot back to Paula Creamer (69), Morgan Pressel (67) Leta Lindley (66) and Maria Hjorth (72).
Ochoa is seeking her first victory since her triumph in the Corona Championship in Mexico in April.
She is seeking her third victory of 2009 - amounting to a virtual dry spell for a player who won 21 titles in the previous three years.
She was four adrift through 10 on Saturday, but finished strong - capping her round with a 16-foot birdie putt at the 18th.
Gustafson is seeking her first LPGA victory since 2003.
"For sure I'm really pleased the way I played today," Ochoa said. "I can't remember when was the last time I hit the ball so solidly. I think I had 18 birdie chances and didn't make any bogeys. I wanted to put myself in a good position for Sunday to give myself a chance to win the tournament.
"I'm happy I'm right up there," added Ochoa, who played without a bogey. "I know it's not going be easy, because Sophie and the other players are really good."
Gustafson turned it on early with four birdies in a five-hole stretch from the second to take a three-shot lead. She drained a 20-footer for birdie at 10 to lead by four.
Ochoa, who birdied five and six, drained a 12-footer for birdie at 12, as Gustafson ended up with a three-putt bogey that saw the Swede's lead dwindle to two.
Ochoa promptly birdied 13, and grabbed a share of the lead with a 15-foot birdie effort at 15.
A birdie at 17 saw Gustafson regain sole possession of the lead, but Ochoa's birdie at the last put her atop the leaderboard going into the final round.
AFP
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