Cristie Kerr shot a career-best 10-under 61 Saturday in the second round of the John Q. Hammons Hotel Classic, the top single-round score on the LPGA Tour this year.

Kerr's course-record 61 at Cedar Ridge Country Club in suburban Tulsa helped her take the lead over Annika Sorenstam, who is the only LPGA player to break 60 in a round. Sorenstam shot a 59 at Moon Valley Country Club in Phoenix in the second round of the 2001 Standard Register PING.

Kerr's previous best was a 62, which she shot last year in the first round of the Longs Drugs Challenge at The Ridge Golf Club in Auburn, Calif.

Three players have shot a 60 on the LPGA tour and five others besides Kerr have carded a 61.

Kerr started Saturday's round at 1 under, six shots behind Sorenstam, but needed only 13 holes to surge ahead. Sorenstam, playing in the group ahead of Kerr, quickly tied it up with a birdie on No. 14, but Kerr also birdied the hole to regain the lead.

Kerr will take a one-shot lead over Sorenstam into the tournament's final round on Sunday. Sorenstam shot a 3-under 68 Saturday.

The 28-year-old Kerr has eight career victories, including two this year _ the Franklin American Mortgage Championship in Franklin, Tenn., and the Canadian Women's Open in London, Ontario. In the latter, she overcame an eight-stroke deficit in the final round, shooting a bogey-free, 7-under 65 for a one-stroke victory over Angela Stanford.

Kerr has finished in the top 10 in 13 tournaments this year and is fourth on the tour money list behind Lorena Ochoa, Karrie Webb and Sorenstam.