Zalatoris, whose reputation as the highest-earning player on the circuit without a title to his name, collected a $2.7 million bonus for his maiden success out of a total purse of $15 million.
After a nail-biting final round which included a stunning putt on the 18th hole to take it to a play-off, the American managed to come out on top in a see-saw three holes.
"It's a little harsh to say it was about time when it's only your second year on Tour, but yes: it was about time," said a happy Zalatoris, who has come agonisingly close to huge wins with second place finishes at three of the four major tournaments.
Full results from the Memphis tournament
This year he finished second at the US Open and PGA Championship and was the highest-ranked player in the world rankings without a trophy so far. The triumph will now propel him into the top ten for the first time in his career.
As well as that, he now finds himself at the top of the FedEx Cup standings heading into the BMW Championship on August 18th, with his eyes firmly set on the $18 million winnings.