The 2021 winners had a combined blemish-free opening round and finishing strongly with birdies on the 17th and 18th at TPC Louisiana.

Americans Patrick Cantlay and Xander Schauffele are the early pacesetters.

Cantlay holed a 25-foot eagle putt early and chipped in from 40 feet for birdie late, while Schauffele contributed six birdies of his own, and their three straight birdies to close gave them a 13-under 59 in fourballs on Thursday to enjoy the clubhouse lead.

It set a tournament record since the Zurich Classic switched to team play in 2017, and the Presidents Cup and Ryder Cup partners were willing to claim a piece of golf's magic number.

"We are going into a format on Friday that we really like – I think Xander and I really like alternate shot. It's one of our strengths for the week, and we're really looking forward to it." - Patrick Cantlay.

"I haven't done it before. I don't think Pat has, either. I'll count in my book," Schauffele said.

They had a one-shot lead over the team of compatriots Matthew NeSmith and Taylor Moore. The group at 61 included Robert Garrigus and Tommy Gainey, and Aaron Rai and David Lipsky.

Masters champion Scottie Scheffler and Ryan Palmer were five shots behind at eight-under.

The second round moves to foursomes, and while alternate is the more difficult of the format, Cantlay and Schauffele have put together a 4-0 mark in their partnerships at the 2019 Presidents Cup at Royal Melbourne and he 2021 Ryder Cup at Whistling Straits.

"It's just the first quarter. We're only one ahead," Cantlay said.

"But we are going into a format on Friday that we really like – I think Xander and I really like alternate shot. It's one of our strengths for the week, and we're really looking forward to it."

The surprise was Garrigus and Gainey, both sponsor exemptions. Garrigus was in the news earlier in the week when Golfweek reported and Golf Channel confirmed with Garrigus that he is applying for a conflicting event release to play in the first Saudi-funded LIV Golf competition.

The PGA Tour has until May 10 to decide whether to grant him a release to play in London a week before the U.S. Open. The top players – that would not include Garrigus, whose world ranking is at No.1043 – have said they are not interested in the Greg Norman-run league offering a $20 million purse and $4 million to the winner.