Molinari, who had taken considerable time off over the last few months to prepare himself for a busy golfing schedule in 2019, produced the best round of the day to win by two over third-round leader Matthew Fitzpatrick while Sungjae Im, Tommy Fleetwood and Rafa Cabrera Bello were another shot back in a share of third.
On a leaderboard dominated by internationals, only one of the leading nine players was American but none would be Australians after a late stumble from Aaron Baddeley cost him a chance of a very high finish.
Baddeley began the final round well and was potentially on track to better his last event finish when runner-up in Puerto-Rico but he would drop three shots late in his round and finish 17th.
Former winner Marc Leishman was the only other Australian to make the cut and finished 23rd.
For Molinari however, he completed a week which had included a hole-in-one in Thursday’s opening round and elevated his status even further in the game after winning his first major at Carnoustie last July.
He all but sealed the win with a 44-foot birdie putt across the green at the last and although many of his nearest challengers still had several holes to play they faced a tough task to catch the leader and so it would prove.
The victory came in his first week as a Callaway player having made the switch following the WGC event in Mexico.
“You know, it was the first week as a Callaway player, so happy to see that the switch I made wasn't that crazy as some people thought,” said the Italian.
“I know the clubs are good for me and I started this week - it's crazy to do it here, to get it done here, at Arnie's place, knowing that my wife and my kids were watching it back home, it's just a special, special one.”
Molinari is also delighted to be near his peak ahead of next week’s Players Championship further up the Florida coast near Jacksonville.
“Yeah, obviously THE PLAYERS coming next week, it's a huge tournament for all of us, obviously the first big event of the season. We're lucky to play great tournaments, but that's definitely a special one. Yeah, I was confident already that my game was at a nice point but obviously it's nice to show it like this on a Sunday.”
In a separate contest within the tournament, Sungjae Im, Sung Kang and Keith Mitchell gained the three positions on offer at this year's Open Championship to the leading three players in the event not otherwise exempt to the third major of the year.
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