Hunter Mahan clinched the Houston Open after winning by a single stroke in a dramatic finish.
Mahan kept his cool on the 18th to edge out Sweden's Carl Pettersson to the title.
Overnight leader Louis Oosthuizen's bid fell apart with a three-over-par 75 and eventually finished third despite a two-shot overnight lead.
The 29-year-old's success is well-timed as he is set to move up to fourth in the world rankings ahead of the Masters on Thursday.
He looks to be the highest-ranked American in Augusta for the first major of the year.
Mahan finished last year's Masters tournament tied for eighth.