Los Angeles - American Charley Hoffman maintained a one-shot lead at the PGA Tour's Houston Open on Friday in the weather-hit second round.
Hoffman had four birdies and two bogeys in his two-under par 70 that put him on 10-under 134.
He was one stroke in front of American Jamie Lovemark, who carded a 68 for 135.
Americans Chez Reavie and Dustin Johnson were in the clubhouse on 136, Reavie posting a 70 and Johnson signing for a 71.
Johnson completed his round shortly before darkness halted play with 27 players still on the course, the result of a 90-minute morning delay because of thunderstorms.
Among those still to finish, Wales' Jamie Donaldson and American Roberto Castro were eight-under for the tournament through 15 holes - tied for third with Reavie and Johnson.
World No 2 Jordan Spieth did little to build momentum for his Masters title defence next week.
Spieth was six adrift on 140 after a one-over 73 on Friday.
The US star, who was supplanted atop the world rankings by Jason Day on Monday, was in the water at two par-fives and struggled on the greens.
"I have to putt better," Spieth said. "I'm losing a couple strokes to the field on putting and normally we're gaining strokes.
"Inside 10 feet, I need to be solid and confident. I can't get into a rhythm. I'm stepping off putts."
Spieth, who teed off on No 10, made bogey on both of the front nine's par-fives, hitting his tee shots on four and eight into the water.
"It just kind of really stinks to keep on making those mistakes," he said.
Leading scores on Friday in the weather-disrupted PGA Tour Houston
Open (Round halted by darkness, to resume Saturday. USA unless noted,
134 - Charley Hoffman 64-70
135 - Jamie Lovemark 67-68
136 - Chez Reavie 66-70, Dustin Johnson 65-71
137 - Will MacKenzie 69-68
138 - Russell Henley 70-68, Charles Howell 69-69, Harris English 68-70
- Scott Brown 65-74, Bernd Wiesberger (AUT) 68-71, Rickie Fowler 69-70,
Lucas Glover 71-68, Andrew Loupe 67-72, Scott Pinckney 66-73
Kim Whee (KOR) 67-73, Henrik Stenson (SWE) 69-71 , Jordan Spieth 67-73,
Luke List 68-72, Patrick Reed 69-71, David Hearn (CAN) 70-70, Kim
Si-Woo (KOR) 69-71, Justin Hicks 66-74, Steve Marino 67-73, Phil
Mickelson 69-71, David Toms 70-70, Stuart Appleby (AUS) 69-71