IRVING (Texas), May 15: American Brett Wetterich held his nerve over the closing stretch to seal a maiden PGA Tour title by a stroke at the Byron Nelson Championship on Sunday.

One off the pace at the start of the day, the 32-year-old from Ohio fired a two-under-par 68 in bright sunshine at the TPC at Las Colinas to finish on 12-under 268.

South African Trevor Immelman, co-leader overnight with Australia's Adam Scott, had moved two strokes clear at the turn in a bid for his own breakthrough Tour victory before falling out of contention.

He dropped three shots in six holes from the 10th and did well to salvage a par at the last, after driving into water, before signing for a 70 and second place at 11 under.

American Omar Uresti, who twice held a share of the lead in the final round, finished a further shot back in a tie for third with Scott after closing with a 68.

Britain's Brian Davis made the biggest move among the early starters after teeing off at the 10th, reeling off six birdies before a bogey at his final hole gave him a best-of-the-day 65 and a tie for eighth at seven under.

Leading final round scores:

268 –Brett Wetterich (US) 66, 64, 70, 68.

269 – Trevor Immelman (South Africa) 68, 67, 64, 70.

270 – Omar Uresti (US) 67, 66, 69, 68; Adam Scott (Australia) 65, 65, 69, 71.

271 – Chad Campbell (US) 72, 65, 65, 69.

272 – Shigeki Maruyama (Japan) 71, 68, 67, 66; Luke Donald (Britain) 69, 66, 69, 68.

273 – Brian Davis (Britain) 70, 68, 70, 65; Rod Pampling (Australia) 71, 69, 67, 66; Jason Bohn (US) 70, 68, 68, 67; Dudley Hart (US) 68, 68, 68, 69; Charley Hoffman (US) 70, 67, 65, 71.

274 – J.J. Henry (US) 67, 70, 70, 67; Shaun Micheel (US) 70, 68, 70, 66; Mathew Goggin (Australia) 68, 70, 69, 67; Arron Oberholser (US) 74, 60, 72, 68; Ernie Els (South Africa) 68, 69, 69, 68; Jeff Sluman (US) 70, 70, 64, 70..—Reuters