Peter Malnati was left fighting back tears after he claimed his second PGA Tour title and first since 2015 with victory in the Valspar Championship.
Malnati carded a final round of 67 at Innisbrook Resort to finish 12 under par, two shots clear of fellow American Cameron Young.
Young, who three-putted the 18th in a closing 68, remains without a PGA Tour victory and has now finished runner-up seven times, including in the 2022 Open Championship at St Andrews.
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Malnati declared: "I told myself I was going to do my best on every shot and that's what I did.
"I was so nervous coming down the stretch and the approach into 16 was terrible... I just can't describe it. It's so cool. It's just amazing.
"You wonder if you're ever going to do it again because it's hard and in the nine years since my last win it's gotten a lot harder too.
"You look at the level of talent out here, guys coming out when they're 20 years old and they're ready to play on this stage and they're so good. So to have this moment it just feels so amazing."
The victory qualified Malnati, 36, for his first career Masters in three weeks, which he called "the realisation of another childhood dream."
"That will be amazing," said Malnati, who entered the week ranked No 184 in the world. "But I think more of what has sunk in to me is, this guarantees me that, this is my 10th season on the PGA Tour, it guarantees me that I'm going to have 12 [years], at least."
Malnati had earlier admitted he enjoyed a massive slice of luck on the 16th, hitting his approach through the green into thick rough but being allowed to drop away from a sprinkler head interfering with his stance.
That meant Malnati's ball ended up on the fringe of the green and he could be heard telling rules official Steve Rintoul: "I feel this is a great break and I want you to be here."
After two-putting from long range for par, Malnati hit a superb tee shot on the par-three 17th to set up a birdie from six feet as Young, in the group ahead, found trouble off the tee on his way to a closing bogey.
Overnight leader Keith Mitchell and playing partner Seamus Power endured final rounds to forget, the pair shooting 77 and 76 respectively to slump down the leaderboard.
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