Tony Finau was solid without being spectacular as he carded a two-under round on the third day at the Houston Open to maintain his four-stroke lead on Saturday.
Finau led by four shots at the halfway point after 10 birdies in Friday's eight-under 62, but the American kept it steady with a bogey-free round that included only two birdies at Memorial Park Golf Course on Saturday.
The main contenders, Patrick Rodgers and Alex Noren, both carded three-over 73s to drop well off the pace at six-under overall but Englishman Ben Taylor emerged into second on moving day.
Taylor looms as the only potential challenger for Finau (15-under overall) ahead of the final day, shooting six birdies in his five-under round-of-the-day 65 to move up the leaderboard into 11-under overall.
The Englishman buried a 21-foot closing birdie putt to finish the day on a high and keep the pressure on Finau.
Taylor is three strokes clear of the next best, with three players tied at eight under; Justin Rose, Wyndham Clark and Tyson Alexander. Gary Woodland and Joel Dahmen are seven under.
World number two Scottie Scheffler could not mount any kind of challenge, with a double bogey on the 16th hole followed by a bogey on the 18th leaving him with one-over 71 to be three-under overall.
Last year's Masters champion Hideki Matsuyama withdrew after nine holes on Saturday due to a neck injury but was not in contention.