The tournament lost its biggest name when world No. 1 Annika Sorenstam withdrew. She has both a bulging and ruptured disc in her back and will miss a month.
'I've been playing with quite a bit of pain for the past several weeks,' Sorenstam said in a statement. 'I couldn't take it much more and decided it was time to see someone after the pro-am yesterday. I withdraw with deep regret as the Ginn Open is one of the finest tournaments we have, and it is in my home town of Orlando.'
Brittany Lincicome is alone in third place after a 5-under-par 67 at the Legacy & Independence Courses at Reunion Resort and Club.
Ochoa, who tied for second last year, started on the back nine and quickly broke into red figures. She knocked her second at the par-5 10th hole into a bunker, where she blasted out to 2 feet to set up her birdie.
She hit a 7-iron to 3 feet for a birdie at 12, but dropped a shot at 13. Ochoa's 3-wood tee shot sailed left into a bush, where she was forced to take an unplayable lie.
At the par-three 16th, Ochoa nearly holed her 7-wood tee ball, but had to settle for a tap-in birdie. She parred her next four holes around the turn, but two-putted for a birdie at the par-5 third.
Ochoa made it two in a row as her wedge shot left her with a 9-footer for birdie at the fourth. She converted that putt, but found trouble at the very next tee. Ochoa's seven-wood let her down on the par-3 fifth as her tee ball missed the green 20 yards right. She chipped to 12 feet and missed that putt to fall to 3 under par for the championship.
Ochoa atoned for the error quickly as she hit a 9-iron to a foot at the sixth. She tapped that putt in and followed with a 15-footer for birdie at the seventh.
At the par-5 ninth, Ochoa tried to reach the putting surface in two, but came up short in a bunker. She blasted out to 5 feet and sank the birdie putt to move into the lead.
'It was a good day,' acknowledged Ochoa. 'I've been working on getting a good result the first day of the tournament. It makes a difference for me and that was a goal today.'
Ochoa had a chance to overtake Sorenstam for the No. 1 place in the Rolex Rankings if the Mexican star would have won the Nabisco Championship. She did not, but with Sorenstam on the shelf for a month, the chances are good that Ochoa will move to first.
'I just want to do my own thing and I'm going to keep doing the same,' said Ochoa. 'I would love for her to be playing. Hopefully she's doing okay and will recover soon and be back.'
Davies got to 2-under par with a 25-foot eagle putt at the par-5 third. She birdied the par-3 fifth hole, but uncharacteristically bogeyed a par-5, the ninth.
On the back nine, Davies reeled off three straight birdies from the 11th to get to minus-5. A birdie at the par-517th put Davies into a tie with Ochoa.
'Today's round is what I've been hoping for rather than the rounds I've had,' said Davies. 'I've been shooting a lot of 1-, 2-unders, which is not good enough out here anymore.'
Davies has not won on the LPGA Tour since the 2001 Wegmans Rochester International, which was her 20th title on the circuit.
'I mean I've won around the world, just not won in the LPGA,' said Davies. 'It's really lack of confidence in the driver.'
Defending champion Mi Hyun Kim, Sherri Turner and Na Ri Kim are tied for fourth place at 4-under-par 68.
Minea Blomqvist, In-Kyung Kim, Reilley Rankin, Tina Barrett, Sarah Lynn Sargent, Hye Jung Choi, Natalie Gulbis and Se Ri Pak are knotted in seventh at minus-3.
Morgan Pressel is playing for the first time as a major champion after her win at the Nabisco Championship, and it was not a memorable round. She shot a 3-over-par 75 and is part of a group tied for 102nd place.
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