The American partnership of Cantlay and Schauffele closed with an even-par-72 in the alternate-shot final round to finish at 29-under 259 at TPC Louisiana.

They broke the tournament record of 27-under set by Cameron Smith-Jonas Blixt and Kevin Kisner-Scott Brown.

Cantlay and Schauffele opened with a record 59 in best-ball play Thursday, and began Sunday at 29-under after shattering the 54-hole record of 23-under.

However, on Sunday their five-shot lead was cut to a single stroke as they stumbled around the turn, but they held their nerve on the back nine to keep local favourite Sam Burns and Billy Horschel at bay.

Burns and Horschel pulled within one stroke after birdies on the 8th, 10th and 11th holes.

The Aussie combination of Jason Day and Jason Scrivener finished in 10th after a disappointing Sunday. PHOTO: Sarah Stier/Getty Images.

But Burns' tee shot on the short par-4 16th found the water and a bogey on the par-3 17th left them three behind.

They shot 68.

Doc Redman and Sam Ryder were third at 24-under after a 67.

Six teams tied for fourth at 23-under while Day and Scrivener signed for a one-over 73 to slide from T-3 overnight to a share of 10th at 22-under.

They were five shots better than last year's champions Smith and Marc Leishman, who rounded out their title defence with a 72 to be equal 21st.

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Day and Scrivener, who went into Sunday hopeful of moving up the leaderboard dropped shots at the 3rd and 5th holes before mixing three back-nine birdies with two more bogeys.

Schauffele and Cantlay could even afford to be unconcerned with a closing bogey as they completed a wire-to-win success.

It's awesome," Schauffele, a five-time winner on the PGA Tour, told CBS.

"I said earlier this week if there's any success I could share with someone it'd be Pat so I'm happy we could get it done."

Defending FedExCup champion and PGA Tour Player of the Year Cantlay, who lost a play-off to Jordan Spieth in the RBC Heritage last week, added: "It was a great week. We had a lot of fun, both on and off the golf course, and we're really happy to get it done."