Ludvig Aberg held a three-shot overnight lead, but the Swede, who still led the field by three with nine to play imploded; his hopes sunk in a couple of the course’s many lakes.
The European Ryder Cup star’s seemingly serene march to the title was abruptly halted by visits to water on the 11th and 12th holes, costing him those three shots.
Fitzpatrick, who had missed makeable birdie chances from 15, 11, 11 and seven feet on four successive holes from the eighth, birdied the 12th and 13th to surge into the lead on 13 under.
But Young stuck with him, also picking up a shot on the short 13th to stay one back.
Young was still one adrift on the notoriously tricky par-three 17th, with its green almost surrounded by water.
But he found the green and rolled in a 10-foot birdie, while Fitzpatrick could only two-putt for par and the players marched to the 18th tee for a final-hole shootout.
Fitzpatrick was welcomed by pantomime boos from the partisan fans who were predictably rooting for their man.
“The crowd was child’s play compared to Bethpage,” said the Yorkshireman, referring to the treatment handed out to Europe’s players at last September’s Ryder Cup in New York.
“If they think that that was anything, then they need to reassess. Get yourself up to New York.
“I knew it was coming. I find it hilarious.”
And while Young elicited cheers of “USA” after crushing the perfect drive 375 yards down the fairway, Fitzpatrick’s went straight and among trees, leaving him unable to reach the green in two.
The Yorkshireman said “I felt like I hit a good drive but once you get out of position it’s difficult to make par”.
