Los Angeles - Jim Herman, seeking a first US PGA Tour title and a berth in next week's Masters, fired a bogey-free five-under-par 67 on Saturday to seize a share of the third-round lead at the Houston Open.
Herman had five birdies at the Golf Club of Houston and was joined on 11-under-par 205 by fellow American Jamie Lovemark, who had four birdies and two bogeys in a two-under-par 70.
Sweden's Henrik Stenson posted the best score of the day, defying difficult windy conditions with a six-under 66 that left him tied for third on 206 alongside Dustin Johnson (70) and Russell Henley (68).
Stenson's seven birdies included putts of 22 and 26 feet on the back nine in a round capped by a 41-footer from the fringe to save par at the last.
"That definitely makes a big difference," Stenson said of his solid putting.
"The first two days I hit the ball quite nicely, but I haven't been putting well. I worked again yesterday afternoon on my putting and I got it going a bit better -- made a couple of beauties out there."
American Roberto Castro was alone sixth after a 70 for 207. Second-round leader Charley Hoffman struggled to a two-over 74 to head a group on 208 that also included Kyle Reifers and Chez Reavie.
World number two Jordan Spieth, tuning up for his Masters title defence next week, carded a two-under 70 to lie five off the pace.
"I felt like I played well," said Spieth, who had five birdies, a bogey and a double-bogey. "We had just some unreal wind flips on the first six, seven holes -- it was flipping back and forth, we were on the wrong end of about six in a row.
"It's really tough to stay patient through that because I was putting good swings on it," said the 22-year-old Texan, whose birdies included a hole-out from a bunker at the seventh.
"But I'm playing really, really solid golf," Spieth added. "It just has yet to come through in a score of six- or seven-under.
"Hopefully that means we're saving them for tomorrow and next week."
While Spieth is warming up for the Masters, Herman and Lovemark will each be trying to punch his ticket to the first major of the year with a first tour win on Sunday.
Lovemark, a 28-year-old former US collegiate champion whose pro career was disrupted by back surgery, made three of his four birdies at the second, third and fourth holes.
His only birdie on the back nine, at the 10th, was followed by his second bogey of the day at the 11th, but pars the rest of the way were enough to give him a share of the lead.
Herman, 38, acknowledged that the pressure would be on Sunday.
"There's a lot to play for," he said. "I'm just going to keep doing what I've been doing."