American Joe Highsmith was clinging to a one-stroke lead when darkness halted the second round of the US PGA Tour Puerto Rico Open on Friday.
Highsmith teed off on the 10th at Grande Reserve Golf Club in Rio Grande and after two birdies in his first eight holes eagled the par-five 18th.
He bounced back from a bogey at the first with three birdies in his next four holes and was at 13-under par through 15 holes when play was halted.
That put him one in front of half a dozen players who had made it into the clubhouse on 12-under, a group featuring Germany's Matti Schmid, Americans Kevin Streelman, Brice Garnett and Erik Barnes, Puerto Rico's Rafael Campos and Japan's Rio Hisatsune.
Schmid carded a seven-under-par 65, Garnett and Barnes both shot 66 and Streelman, Campos and Hisatsune all posted 67s.
Highsmith, a 23-year-old chasing a first tour title, had shared the overnight lead with Scott Piercy, managing to get in the clubhouse on seven under on Thursday before thunderstorms halted play for two hours.
The tournament is still playing catch-up, with round two due to resume on Saturday morning with round three to follow.
The tournament is played opposite this week's Arnold Palmer Invitational at Bay Hill, one of the PGA Tour's signature events designed to showcase the game's top talent.