Ross McGowan held his nerve on the final green to win the Italian Open by one stroke as Jonathan Caldwell enjoyed a career-high finish in a tie for fifth.
McGowan sunk a 20-foot putt on the 18th and then watched as playing partner and fellow Englishman Laurie Canter failed to hole from 12 feet.
McGowan finished on 20 under par after a final-round one-under 71, with Canter tied for second with Belgium's Nicolas Colsaerts.
It was the 38-year-old's first win on the European Tour for 11 years.
Caldwell shot his third 68 of the week to follow up his seventh place in the Scottish Open last week.
Cormac Sharvin had a disappointing 75 to finish joint-60th.
McGowan said: "I'm very happy, not happy with the way I played particularly but I got the ball in the hole which in the past has been my nemesis, so it was nice to be able to do that this week.
"I didn't really foresee this, my form hasn't been great. But I felt like I was playing better, definitely around the greens.
"I think I'm going to have to go now and have a nice big glass of red wine and think about what's next."
McGowan and Canter entered the final day three shots clear of the field in a share of the lead but they had been caught by the eighth as they both turned in 37, with McGowan following a double-bogey after finding water on the fifth with an eagle from 14 feet on the next.
Birdies on the 10th and 11th handed Canter a two-shot lead but he made back-to-back bogeys on the 14th and 15th, with McGowan's brilliance from the sand on the next handing him the solo lead for the first time all week.
Canter hit back with a tee shot to six feet on the 17th and it was a three-way tie as the last group played the 18th, with Colsaerts making a birdie ahead of them.
McGowan laid up and left himself 20 feet for birdie and, while Canter found the greenside rough in two, he could not get up and down and McGowan sealed victory with a birdie.
Canter carded a 72, with 2012 Ryder Cup hero Colsaerts signing for a closing 68 to finish one shot ahead of German Sebastian Heisele.