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.
Fitzpatrick, who shared the 54-hole lead with sixth-ranked Rory McIlroy of Northern Ireland, shot 71, while Tommy Fleetwood of England and Sungjae Im of South Korea both totaled 68 to finish three shots back in a tie for third with Rafa Cabrera Bello of Spain, who closed with a 69.
According to NBC Sports, Molinari made a PGA Tour-career-best 146 1/2 feet of putts in the final round.
"Probably have to say my best putting round ever". "It's great to get it done here at Arnie's place with the wife and kids watching on TV at home".
"I'm playing well, I'm getting myself into contention every week", said the Co Down man who will play just twice more before he seeks that elusive Masters victory at Augusta National in five weeks. "The course was firm and fast [Saturday] and I knew it wasn't going to be easy for the guys in the lead, so I thought there was an outside chance".
The script was written for Rory McIlroy to make a successful defence of the title he won in such brilliant fashion 12 months ago but McIlroy endured another wretched day when he couldn't hole a putt worth the name.
His T6 finish with Wallace, Sung Kang and last week's victor Keith Mitchell is McIlroy's fifth consecutive top 10 on Tour. He then just missed the green on the par-four 16th but holed a huge putt for an eagle to take the lead before missing a good birdie chance on the last. "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 golf, a missed cut from a player owned by almost half the field can really make the difference in tournaments.
PGA Tour 2019: Final leaderboard for Arnold Palmer Invitational (F. Molinari winner)
Matt Wallace finished alongside McIlroy, though the Englishman was left to count the cost after bogeys at the closing two holes.
All that mattered was that it dropped, capping off a five-shot rally with a final round no one imagined on a fast Bay Hill course with putting surfaces that looked closer to white than green, making it hard for anyone to get it close to the hole.
Molinari pointed to the first of his last four victories for sparking his turnaround.
Despite withdrawing from Bay Hill with a neck injury, Tiger Woods moved up one spot to No. 11 in the latest rankings as he gets set to make his competitive return this week at TPC Sawgrass.
Meeting with the media and donned in an Arnold Palmer red alpaca cardigan, Molinari toasted Palmer with one of the legend's favourite drinks, Ketel One vodka, on the rocks, with a twist of lemon. "I think obviously confidence has to do a lot with it". Coetzee eagled the last for a 68 that made it five top-10finishes at this event, with Bezuidenhout and Campillo also recording four under par rounds.
"Finding motivation was easy after previous year", Molinari said. I get into the events that I'd like to be into again, the schedules change, I'm no longer having to pick and choose.More news: Israeli authorities to reopen Al-Aqsa Mosque compound
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