Defending champion Lorena Ochoa fired a six- under 66 on Saturday and moved into sole possession of the lead after the third round of the Navistar LPGA Classic.

Ochoa finished at 16-under 200 and is three strokes clear of Sandra Gal, who also managed a 66 on Saturday, at The Senator Course at Capitol Hill Golf Club.

Janice Moodie and Brittany Lang both had rounds of four-under 68 and are tied for third place at 12-under 204.

Alexis Thompson, the 14-year-old amateur who shared the second-round lead with Ochoa and others, struggled on Saturday. She carded a two-over 74 and fell into a tie for 13th place at eight-under 208.

Thompson birdied her first hole Saturday to take the lead at 11-under par. She bogeyed No. 3 and double-bogeyed the sixth to fall down the leaderboard, but a birdie at eight stopped the damage.

The 14-year-old parred her next eight holes, but a bogey at the par-five 17th left her well down the leaderboard. Thompson's chances at becoming the youngest winner on tour are remote barring an extremely low round on Sunday.

"It's just one of those days that your game is off. That's golf," said Thompson. "You have those days where it just doesn't feel right, and that's what it was like."

Michelle Wie shot an even-par 72 and is in the large group with Thompson at minus-eight.

Ochoa was part of that large group that shared the overnight lead, but the world's best and defending champion only managed six pars to open her third round.

At the par-three seventh, Ochoa hit a five-iron to 12 feet. She ran home the birdie putt and that kicked off three straight birdies, including a two-putt at the par-five eighth and a 15-footer at nine.

"Once I made that, then I just gave myself more of a better feeling and a good rhythm," said Ochoa, referring to her birdie at seven.

Ochoa made a 10-foot birdie putt at the 12th and that tied her for the lead with Lang. Ochoa broke away from the tie when Lang bogeyed 15 and 18 and she sank a 12-footer for birdie at the 14th.

Ochoa came up short of the green with her second at the par-five 17th. She chipped to 12 feet and converted the birdie effort to give herself a three- shot cushion.

"I'm really pleased," said Ochoa. "I'm happy I'm in a good position, and tomorrow's going to be just a new day. I'm going to try my best to win the tournament."

Ochoa hasn't done that in some time. She has two wins this season on tour, but the last one came in late April.

"Middle of the year was a little bit slow," acknowledged Ochoa. "I played good the last few weeks and missed some chances."

Ochoa has the 54-hole lead and that's been a good thing for her the last two years. The last time Ochoa squandered the third-round lead on tour was two years ago at this championship and in that time she's won 10 times with the third-round lead.

Ji Young Oh (65), Maria Hjorth (68) and Yani Tseng (71) are knotted in fifth place at minus-11.

Laura Davies and Giulia Sergas, second-round co-leaders with Ochoa, Thompson and Tseng, both had even-par 72s on Saturday and are tied for eighth with Allison Fouch, who carded a four-under 68. The trio is knotted at 10-under 206.

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