Tom Lewis fired a sensational closing 65 to win the Portugal Masters, only his third tournament as a professional, by two shots from Rafael Cabrera-Bello.
On a low-scoring week, the Englishman started the day four shots off the lead and birdies at the 1st and 5th kept him in touch with the leaders.
But as the pre-round favourites stuttered on the back nine, Lewis came alive and produced a blistering run of five birdies in six holes from the 12th to the 17th to break the deadlock at -18 and set the target of -21.
The 20-year-old faced an anxious wait as the leaders played the remaining holes but no one could surpass his impressive total.
Cabrera-Bello birdied 15, 16 and 17 to finish alone in second. A group of five players, including England's David Lynn, tied for third.
The stunning victory and the €416,660 winners' cheque guarantees the 20-year-old his European Tour card for the next two seasons and lifts him to 53rd in the Race to Dubai and 166th in the world rankings.
"I've not thought about the money - I was thinking about winning," he said shortly afterwards.
"I would not have expected this at all," he added. "I was really dreading going to the qualifying school at the end of the year, but it looks like I've skipped that."