Park carded eight birdies to come from five strokes back of second round leader Andrews. The 21-year-old took the lead on the par-3 17th after her 8-iron left her with a three-foot birdie putt.
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Andrews had the opportunity to tie Park on the 18th but her 50-foot birdie try came just short of the hole.
'I didn't look at the scoreboard until 16, so I really had no idea how Donna was playing,' said Park. 'I just was thinking, try to keep the score, like what I was thinking this morning - five-under par.'
Park was 4-under through nine holes before finding trouble on the par-4 10th. After hitting out of a bunker, she two-putted for a double- bogey.
'My feet were outside of the bunker,' she said. 'The ball was below my feet. I had lots of sand under my ball. I hit it kind of fat, I think. Just didn't get on the green.'
Park recovered by birdieing four of the next eight holes to surpass her previous career low by two strokes.
Andrews was even for her round with two birdies and two bogeys after a career-low round of 62 yesterday. Her bogey on par-5 3rd came after her lob-wedge to 10 feet spun back to stop 45 feet from the cup.
'I was in some bad spots off the tee and some bad spots on the green,' said Andrews. 'Plus, I just didn't make any putts today. I made a million miles of putts yesterday, and that's the difference.
'I someone were to say I could take even-par today and walk away I would have said 'okay.' I mean, to shoot 62, and then shoot even is not, to me, a bad round,' she said. 'I just hit a couple of bad shots, but I made some great up and downs as well.'
Andrews' second-place finish is her best in 2001, but she remains winless since the Longs Drugs Challenge in 1998.
The duo of Andrews and Park finished well ahead of the rest of the pack on a weekend in which only nine players finished below par.
Rachel Teske posted a 71 to finish in third at 3-under 207 followed by Nancy Scranton, who finished at 2-under 208.
Five players tied for fifth place at one-under 209, including Wendy Ward who was tied for second after three rounds. She joined Annika Sorenstam (69), Becky Iverson (70), Barb Mucha (70), and Yu Ping Lin (71) eight shots off the lead.
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