The Mexican star seeking her first Women’s Open was happy to take advantage of her early tee time. Her previous best start in an opening round was a ninth in 2003.

“It’s always hard, you have to be 100 percent at 7:30 in the morning,” she said. “I’m just glad I beat it today, and will try to do the same tomorrow.”

On the par-4 second hole, Ochoa rolled in one of the longest putts of her career — a 50-footer that moved right, left, up and down before falling for a 3.

Kerr hit 15 greens and 10 fairways in a round of three birdies and a bogey, using her knowledge and confidence of being a former Women’s Open champion on the challenging Old Course. She drained birdie putts of 15, 12 and 8 feet and shrugged off her only bogey.

“I’m an Open champion, I know what to expect,” Kerr said. “You have to take what the course gives you at a U.S. Open. You try and be aggressive when you can and most of the time you can’t be.”

Reynolds, a two-time winner on the Futures Tour and the leading money winner on the LPGA’s developmental tour, had four birdies and two bogeys. She had a chance to take sole possession of the lead, but missed a birdie putt at the 18th.

She’s enjoying the ride.

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“I was pretty nervous,” Reynolds said. “It was a good feeling, but then again, coming in under the radar and leading at the U.S. Open after the first round is pretty awesome.”

Reynolds opened with a birdie at the first and made a strong par save at the second hole after driving into a fairway bunker. She hit a 7-wood to about 45 yards and got up-and-down.

She used pinpoint accuracy with her approach shots to move into contention, hitting to within a foot at the first, 3 feet at the eighth and 8 feet on the 14th. She also got up-and-down from a greenside bunker at No. 12.

Alexis Thompson is the low amateur after a first-round 71, her finest showing in the first round after missing the cut the last two years. The 14-year-old from Coral Springs, Fla., is the reigning U.S. Girls Junior champ. In 2007, she was the youngest Women’s Open qualifier in history at age 12.

Thompson is tied with LPGA Championship winner Anna Nordqvist, Candie King, Eun Hee Ji, Kristy McPherson and Young Kim.

Former champion Laura Davies, who received a special exemption that extended her streak of competing in championships to 24, opened with a 1-over 72, as did 14 others, including Paula Creamer, Christina Kim, Brittany Lincicome and three amateurs.

Defending champion Inbee Park opened with a 4-over 75, and two-time champion Juli Inkster made her 30th straight Open start and shot a 7-over 78.

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