Updated

By Larry Fine

ROCHESTER, New York (Reuters) - American Cristie Kerr stretched her lead to a record eight strokes after the LPGA Championship third round on Saturday.

The 32-year-old, who won the 2007 U.S. Open, will climb from fifth to first in the world rankings if she wins and number one Ai Miyazato of Japan fails to finish in the top two here.

Miyazato was tied for 24th, six strokes off second spot, with one round to go at the second women's major of the year.

"You can't rest on your laurels," Kerr told reporters. "I'm going to go out and again try to shoot in the 60s.

"It's an honor to be in position to do it. I've just got to keep going."

Kerr began a rainy day at Locust Hill Country Club with a five-shot advantage and a three-under 69 gave her a 13-under total of 203.

Her lead over Japan's Mika Miyazato, no relation to Ai, South Korean Kang Jimin and Spanish rookie Azahara Munoz eclipsed the 54-hole tournament record of seven strokes set by American Mickey Wright in 1961.

Shin Jiyai of South Korea was on 212 alongside compatriot Kim Song-hee.

PERFECT PUTTING

"It's amazing," 2008 British Open champion Shin said of Kerr's performance. "I think her putting is perfect. It looks so easy."

Mika Miyazato, 21, was three shots off the pace after 10 holes but Kerr responded with three birdies in a row.

The Japanese then double-bogeyed the par-four 18th after hitting three shots into deep rough.

"I got mad that I bogeyed 10 and I got on a run," said Kerr. "I just want to keep my foot on the gas."

Earlier, Kerr bounced back from a bogey at the second with back-to-back birdies from the third.

Under the threat of stormy weather in the afternoon, the 73 players who made the cut returned early on Saturday morning to play in threesomes off split tees.

(Editing by Tony Jimenez)