Billy Horschel and Scott Piercy combined for a closing round of five-under par 67 to win the PGA Zurich Classic of New Orleans by one stroke over fellow Americans Jason Dufner and Pat Perez.
The Horschel-Piercy pairing rallied from a three-shot deficit to start the alternate shot format final round, vaulting into the top spot with a 22-under par total of 266.
"This means a lot to me," said Horschel. "My game hasn't been great in the last year.
"We both put a lot of hard work into our game. This validates all the hard work."
The US duo were one of 17 teams within five shots of the lead at the start of Sunday's second foursomes round at TPC Louisiana. The teams played a best-ball format in rounds one and three.
Playing under perfect conditions with sunshine and temperatures in the low 80s Fahrenheit (26C), Dufner and Perez finished one shot back in second with a final-round 68.
South Africans Charl Schwartzel and Louis Oosthuizen were another stroke back in third with a 68.
Tommy Fleetwood-Chris Paisley made an eagle-three at No. 18 to shoot a 69 and finish tied for fourth.
Third round leaders Kevin Kisner and Scott Brown, who lost in a playoff last year, slumped to a 77 and finished in a tie for 15th, seven shots off the pace.
Piercy drained a three-foot putt for par on the final hole to secure the win, but Horschel had the hotter putter of the two this week.
"I putted really well the last couple of weeks," Horschel said. "I said 'Scott just get me on green'. I felt like every putt was going to go in the hole."
"We are excited. I'm excited," said Piercy of the win.
They birdied their first two holes Sunday and then added two more birdies to begin the back nine as they went head-to-head against Dufner and Perez down the stretch.
"I knew my partner was hitting good shots," Piercy added. "I kept trying to put it in right spot for him to do something good with it. To get back is nice and to do it with a good friend is even better."
Kisner and Brown faltered late with a bogey and double bogey on 15 and 16.
Dufner had a 14-foot putt to force a playoff on 18 but missed it.
Billy Horschel (L) and Scott Piercy pose with the trophy and commerative belts after winning the Zurich Classic at TPC Louisiana on April 29, 2018