Billy Glasson, hobbling painfully on oft-damaged knees, shot a 3-under-par 68 Thursday to retain the lead after two rounds of the Panasonic Las Vegas Invitational golf tournament.
Glasson rolled in a 40- to 50-foot birdie putt on his final hole at the Las Vegas Country Club and finished two rounds in 130.
"It's so hard to come back after shooting a 62 (the career-best score he had in Wednesday's opening round) and put a good round together," said Glasson, 24, who is in his third year on the PGA Tour.
"Overall, it was a good, solid round. I'm happy going into tomorrow," said Glasson, who has undergone surgery four times, the latest Dec. 24, on knees damaged in schoolboy athletics.
Glasson holds a one-shot lead over Tom Watson in this five-day, 90-hole tournament that offers $1,042,000 in prizes.
Watson shot a 65 on the Tropicana Country Club course and completed two rounds at 131.
Frank Conner, with a 68 at Desert Inn, was third at 134. He was nine-under par.
Tied at 136 was a group that included Tom Kite, Tim Simpson, Mike Smith and Fred Couples.