MORELIA, Mexico : Top-ranked Lorena Ochoa, seeking a third title in four years at her homeland LPGA event, fired a four-under par 69 to hold a one-stroke lead after 54 holes at the Corona Championship.

Defending champion Ochoa fired eight birdies but also had two bogeys and a double bogey in a roller-coaster third round to stand on 20-under par 199, one stroke better than Norway's Suzann Pettersen, who fired a 67 Saturday.

"I was aggressive, but I can't be perfect every day," said Ochoa, who had notched bogey-free 65s in the first two rounds. "I missed a couple of shots, and that's just the way golf is.

"I'm still happy because I'm still on the lead and the goal is to remain there. Sunday will be complicated. Nothing is going to be easy. Suzann has the desire. So do I. I have to respect her."

Overnight leader Ochoa opened with a birdie, gave back a bogey on the next hole but sank back-to-back birdies at the fourth and fifth and three birdies in a row starting at the ninth.

A bogey at the 12th and double bogey on the par-3 14th sent Ochoa stumbling, but she regained her form with birdies at the 15th and 17th holes to finish atop the leaderboard.

Pettersen enjoyed a bogey-free day, her only bogey so far this week coming on the fourth hole of her opening round.

The European standout birdied the par-3 sixth, eagled the par-5 eighth and birdied the par-4 ninth plus the 12th and 15th to stay on Ochoa's heels.

She was unable to convert a short birdie putt at 18.

"Whatever happened, happened, there's nothing you can do about it," she said. "I'm happy because there are still 18 holes to play.

"It was a good round, not perfect. I managed to gain ground on Lorena, which was one of my goals. ... Hopefully tomorrow, I can go out and shoot as low as I can."

South Korea's Na Yeon Choi was third on 204 with Americans Wendy Ward, Irene Cho and Morgan Pressel sharing fourth on 205.

Choi was delighted with her position.

"Today, I played really good," she said. "I think everything that I made was really good today, and it put me in a really good position for tomorrow in the final round."

However, she said she wouldn't change her focus just because of her position on the leaderboard.

"I don't think the important thing is to win," she said. "For me, I really just want to keep it rolling. I just have to trust in myself."

- AFP/vm