SANTO ANTONIO DA SERRA, Portugal (AP) -- American Peter Uihlein won the Madeira Islands Open on Sunday in his 16th European Tour start for his professional title, closing with a 4-under 68 for a two-stroke victory.

Uihlein, the former Oklahoma State star who won the 2010 U.S. Amateur, birdied four of his last eight holes to finish at 15-under 273 at Santo da Serra.

"I'm just thrilled," Uihlein said "To do it playing well on the back nine, coming down the stretch, is sweet. ... I just knuckled down I guess. It was all putting that did it today, I was just trying to free up and they started to roll in so it was nice."

The 23-year-old Uihlein earned a European Tour exemption through next season. His father, Wally Uihlein, is the chief executive golf apparel and equipment manufacturer Acushnet.

"You grow up quick out here and that was the main reason I came over," Uihlein said. "It's been a good process so far and hopefully I can keep going."

He has three top-10 finishes in seven European Tour events this season.

Denmark's Morten Orum Madsen had a double bogey on the 18th for a 67 to tie for second with Chile's Mark Tullo. Tullo, the third-round leader, had a hole-in-one on No. 4, but had four bogeys in a 71.

Scotland's Craig Lee closed with a 71 to finish three strokes behind Uihlein.