Brendon Todd made birdies on the final two holes of his round to earn a two-shot lead on the second day of the Byron Nelson Championship.
The 28-year-old found his form with the putter at the crucial stage to climb to the top of leaderboard, with a group of eight players just two strokes further back.
Among the players tied for second in Texas is Martin Kaymer, who continued his good form following his win in the Players Championship by finishing on six-under-par at the halfway stage.
Paul Casey ensured he was on level terms with Kaymer thanks to a remarkable 27 shots on the back nine, which included six birdies and an eagle.
A disappointing round of 73 from first-round leader Peter Hanson saw him fall back to two-under, while David Duval failed to make the cut despite a promising start on Thursday.