LOS ANGELES (AFP) - American Charley Hoffman maintained a one-shot lead at the US PGA Tour's Houston Open after Saturday morning's conclusion of the weather-hit second round.

Hoffman had four birdies and two bogeys in his two-under par 70 on Friday 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 also reached the clubhouse before darkness fell on 136, Reavie posting a 70 and Johnson signing for a 71.

Johnson completed his round shortly before play was halted with 27 players still on the course, the result of a 90-minute morning delay because of thunderstorms.