Havret, 24, carded a 69 to end at 20-under-par 268, one shot better than Bradley Dredge (69), and three lower than four others, including defending champion Ian Poulter and Englands Mark Roe.
For the year, Havret moved to 56th on the Volvo Order of Merit list thanks to his first-place check of approximately $150,000.
He also became the second winner from France this year, as his older countryman Thomas Levet won the Victor Chandler British Masters earlier in the season.
It was very, very hard, Havret admitted after his round. I have never known this kind of pressure before.
Those words ring strong indeed, as Havret is a three-time French Amateur champion and also a one-time winner of the European Amateur.
Yet, he showed he is more-than capable of competing on the big tour, as he rattled in three birdies over his last eight holes to wrap the day up.
It feels so good, he said. I didnt expect to win in my first season. My goal was to keep my card.
He certainly exceeded that goal this week in Sardinia, as did Roe, who charged home with a gorgeous 66 to end in joint-third. The finish was good enough to move him from 131st on the money list all the way to 111th, assuring his full-time playing privileges for 2002.
That is the best performance of the year by a long stretch, said the happy Englishman, who will be marching into his 18th season on the tour next year.
Several other players locked up their full-time playing privileges in 2002 by finishing inside the top-115 on the money list.
Included in that mix was Christian Cevaer, whose tie for 38th-place this week saw him finish at No. 115.
Defending champion Poulter had already guaranteed his status for next year thanks to an earlier win at the Moroccan Open.
Yet, the youngster was almost successful in the defense, as he went out in 5-under on his round of 67, which included a hole-in-one at the 170-yard par-3 14th.
Ive given it my best shot, he exclaimed after the round. I missed a couple of putts coming in but overall it has been a pretty good week.
It was also a good week for Dredge, whose 69 on Sunday and outright second boosted him to No. 71 on the Order of Merit.
No one could be smiling bigger than Havret, however.
Said the newly-crowned champion after the round: I want to have more experiences like this soon. This is why we play golf.
Full-Field Scores from the Atlanet Italian Open.