IRVING, Texas — Louis Oosthuizen is still looking for a remedy for his recurring back issues.
A victory at the Byron Nelson Championship would make him feel much better.
"The last year and a half was really frustrating," he said.
Oosthuizen birdied four of the last five holes for 6-under 64 on Saturday and a share of the third-round lead with Brendon Todd. The 2010 British Open champion had the low round of the day after recovering from bogeys on two of the first four holes.
"I made a nice birdie on 5 and just really made some good putts," Oosthuizen said. "Every opportunity I had for birdie I actually made. My eye was good (Saturday), and I hit a lot of them really close."
Todd made 12 straight pars before holing a 4-foot birdie at No. 18 for 68 to match Oosthuizen at 10-under 200.
On the morning of the Nelson's final round last year, Oosthuizen withdrew because of a neck issue. He missed extended time last season and is still bothered by the back, though he won at home in South Africa in January.
Mike Weir, James Hahn and Gary Woodland were one back.
"That's what I've been working toward the last few years, to get myself back here in this position, and looking forward to the challenge," said Weir, a 44-year-old left-hander.
Weir — the 2003 Masters champion who hasn't had a top-25 finish since 2010, when the Canadian had an elbow injury — shot 67 while missing 4-foot putts on Nos. 15 and 16. Hahn's 65 included five birdies in a row on the back nine. Woodland shot 66.
LPGA: Lizette Salas moved into position for her first tour victory, playing 25 holes in 6-under par to take a three-stroke lead in the Kingsmill Championship in Williamsburg, Va. She shot 3-under 68 in the completion of the rain-delayed second round and birdied three of the last five holes in the afternoon for a season-best 65. She had a 13-under 200 total on Kingsmill Resort's River Course. South Korea's Hee Young Park (69), the second-round leader, was second.
CHAMPIONS: Kenny Perry shot 3-under 69 at Shoal Creek to take a one-stroke lead over John Inman (66) after the third round of the Regions Tradition in Birmingham, Ala. Perry, who had a 7-under 209 total, is seeking his third Champions major title after winning the Senior Players Championship and U.S. Senior Open in consecutive tour starts last year.