On a cold and windy Florida day, Gustafson sandwiched a double bogey at the ninth in between four birdies for a round of 2-under-par 70. At 14-under for the tournament, the 27-year-old Swede has a four-shot advantage entering Sunday's final round.
That's the good news. The bad? Karrie Webb's in second place.
Webb birdied two of her final three holes Saturday en route to the low round of the day, a 4-under-par 68.
Juli Inkster (69) and Vicki Goetze-Ackerman (70) are tied for third at 8-under, six shots back of Gustafson. Inkster is in search of her 26th career LPGA victory, while Goetze-Ackerman is still stalking win No. 1.
Mi Hyun Kim began the day two shots off the lead, but bogeyed the par-5 11th and never recovered. The first-round leader played her final eight holes in four-over to fall to 7-under for the event.
Kim's third-round 73 has her in a six-way tie for fifth place with Beth Daniel (71), Heather Bowie (72), Pat Hurst (72), Meg Mallon (72) and Dottie Pepper (72).
Saturday's blustery conditions were ideal for Gustafson, who stated she enjoyed the windy weather following a career-best 64 in the second round. It showed on the front nine, as the tall, athletic Swede birdied the 7th and 8th holes to claim a four-shot cushion at 14-under.
But she gave both strokes back at the par-4 9th, when her approach from 162 yards found the water. Forced to take a drop, Gustafson flew her fourth shot over the greenand and eventually carded a double-bogey 6.
Her lead was back to two, but not for long. Gustafson nearly holed her second shot at the 10th, and then recorded a second successive birdie at the par-5 11th.
Kim also birdied the 10th to stay within two; however, the 11th proved to be her undoing. The diminutive South Korean lost two strokes to her playing companion when she bogeyed the par-five.
Visibly frustrated, the three-time LPGA victor then proceeded to double bogey the par-3 15th and bogey the par-3 17th.
Meanwhile, Gustafson parred her final seven holes to finish the day at 14-under, seven shots clear of Kim.
'I played good, and I think this wind was tougher yesterday,' said Gustafson, who won twice in 2000. 'I like bad weather. It makes it harder for others to catch me.'
Gustafson won't have to look over her shoulder to see if Webb is gaining ground on Sunday. They'll be paired together in the final group.
Webb carded five birdies to just one bogey in the difficult scoring conditions; capping her round with birdies at the 16th and 17th holes.
'I feel like I'm in a good position,' said Webb, who won seven times in 2000. 'The weather isn't supposed to be good tomorrow. If I have a round like today - anything can happen.'
Sunday's forecast calls for more wind and even colder temperatures. The final twosome is scheduled to tee off at 1:00 pmET.
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