SAN ANTONIO (AP) -- Nathan Green got off to a rocky start Thursday in the Valero Texas Open. It ended up jump-starting the best round of the Australian's PGA Tour career.

"I didn't feel really good before the round started and then on the first hole I snapped my drive. It hit a rock and bounced back in the fairway," Green said. "From there, everything went pretty well."

Winless in three seasons on the PGA Tour, Green birdied nine of the first 16 holes before dropping a stroke on the par-3 17th and closing with a par for an 8-under 62 and a two-stroke lead over Olin Browne and Paul Claxton.

Claxton and Browne, a three-time tour winner, had bogey-free 64s in sunny and warm conditions on La Cantera Golf Club's Resort Course.

"This course is right up my alley," said Browne, who tied for second in the 2005 tournament. "I hit every green and only had one shaky putt."

Tim Herron, Greg Kraft, Patrick Sheehan, Jason Gore, Nick O'Hern and Chad Collins opened with 65s, and Paul Goydos and Bob Tway topped a group at 66.

Defending champion Justin Leonard, the former University of Texas star seeking a record fourth victory in the event, shot a 70.

"I hit the ball pretty well off the tee, but didn't make any putts," Leonard said. "The greens weren't as good as they have been, but they were good enough to make putts."

Green shot a 5-under 30 on the front nine, then pulled away from the field with birdies on No. 2 10, 13, 14 and 16 for a four-shot lead.

"It was just one of those days were everything went right," said Green, who tied for second in the 2006 Buick Invitational for his best PGA Tour finish. ""I had two months were I couldn't seem to get anything right, so this was nice to see."

Green recently moved to the Dallas suburb of McKinney to ease his travel burdens and said playing in his adopted home state was a relief.

"I'm not a big fan of planes, so we drove down here Tuesday and it was very relaxing," Green said.

Starting at the par-4 sixth hole, he birdied five holes in a row with putts all 15 feet or shorter. His longest putt of the day came on the par 4 16th, when he rolled in a 24-foot birdie try.

Herron won the 1997 tournament.

"I don't have any problems with conjuring up good memories here," Herron said. "Of course, I made some putts, which helps as well."

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