Peter Malnati carded a bogey-free seven-under 65 to lead by one shot at the Houston Open during a second round suspended due to darkness.
The American finished at 10 under overall and ahead of Talor Gooch, 27, who has five holes left in his second round.
The 32-year-old Malnati stole the lead from his compatriot, who the previous day had equalled the lowest round of his career with an eight-under 64.
Malnati had to battle windy conditions from mid-morning following a two-hour rain delay.
The Indiana native, who was not sure if he would even compete in Texas as his wife is due to give birth to their first child in a fortnight, is chasing his second PGA Tour victory after winning at Sanderson Farms four years ago.
Seamus Power made the cut by one shot despite slumping to a 76. The Waterford man had three birdies and three double-bogeys on his front nine and went birdie, bogey, bogey from 15 through 17.
His 67 on Thursday ensured he only fell to one-under-par however.