Annika Sorenstam dropped her first shot of the tournament at the final hole of her third round but still maintained her three-shot lead in the Michelob Ultra Open.
On a day when she was expected to face a close battle with playing partner and world number one Lorena Ochoa, Sorenstam shot a 69 for a 14-under-par total of 199.
The Swede's nearest challenger is South Korea's Jeong Jang, who also shot 69.
American Solheim Cup player Christina Kim was in third place on 10 under with Sweden's Maria Hjorth alone in fourth on eight under. They both shot 66 - the low rounds of the day.
Ochoa, tied for second at halfway, finished with a 74 and slipped to joint 10th on six under.
England's Karen Stupples underlined her standing as the leading British player in America this year with a solid 70 and was in a five-way tie for fifth place on seven under .
She made a great start to the round with four birdies in the first 11 holes, but dropped shots at the 12th and 13th.
Wales' Becky Morgan, who was another Briton in the top 10 at halfway, slipped back to three under par and tied for 25th after a slightly disappointing 74.
An injured Sorenstam lost the world number one ranking to Ochoa last year but is now in prime position to claim her third victory on the LPGA Tour this season.
She won in Hawaii in February and added the Stanford International title - her 71st career win - in Miami two weeks ago.
"It was slightly disappointing to drop a shot at the last," said the 37-year-old.
"But I'm feeling really good about my game and happy to be in this position going into the last round. But there's still a long way to go."
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