Tim Herron figured he was on the verge of a great round. He just didn't know it would be his lowest score in three years, a 9-under-par 63, or that it would come in the first round of the Buick Challenge.

After warming up in the rain, "Lumpy" got on a roll by taking only 23 putts on the soft greens of Callaway Gardens for a two-stroke lead over Phil Mickelson and five others yesterday in Pine Mountain, Ga.

Mickelson, playing the Buick Challenge for the first time in 10 years, also had a good day on the greens, but most of the focus was on the club in his hands -- a new putter that looked like a branding iron.

It was designed to get the ball rolling immediately, and it helped Mickelson to a 65. He was tied with Rocco Mediate, Bob May, David Gossett, Ben Crane and Michael Long, an alternate who didn't know he was playing until 20 minutes before he teed off.

Herron started on No. 10 and played the back nine in only 2 under, but an eagle on the 508-yard second hole -- he hit a 6-iron to four feet -- got him going. He played his final nine holes in 29, tying the record on the Mountain View Course.

"It was a great stretch, and I knew the cylinders were starting to run," Herron said. "To play like that is why we play golf. I wasn't even thinking 29. I just tried to birdie as many holes as I could."

It was his best score since a 62 in the final round of the 1999 Greater Hartford Open, and his best start in a PGA Tour event since a 10-under 62 in the first round of the 1996 Honda Classic. He went on to a wire-to-wire victory, his first on tour.

Herron hasn't won since 1999, although he wasn't surprised by his score. The man known as "Lumpy" for his roundish physique is coming off a tie for fourth in the Disney Golf Classic after rounds of 66-65-66-65.

"I knew it was coming. I didn't know it was going to be today," he said.

* EUROPE: England's Lee Westwood shot a 7-under 64 for a one-stroke lead after the first round of the Madrid Open. Padraig Harrington, Brian Davis and Maarten Lafeber shot 6-under 65s, and were one stroke off the lead.

* SENIORS: The first round of the Senior Tour Championship in Oklahoma City ended early after heavy rain made many of the greens unplayable. All but two groups had teed off when the horn blew.