Spanish duo Jon Rahm and Sergio Garcia will begin Europe's bid to retain the Ryder Cup after the first four foursomes pairings were revealed at Whistling Straits.
Rahm and Garcia will take on close friends Justin Thomas and Jordan Spieth, elected to lead off for the United States in a mouth-watering opening match after impressing at Le Golf National in 2018.
Europe captain Padraig Harrington admitted that he had decided on his pairs for the opening morning session in Wisconsin long in advance of the event.
Harrington defends selection as he benches McIlroy for Saturday foursomes
The Irishman also combined Ryder Cup rookie Viktor Hovland, the first Norwegian to play in the event, and veteran Paul Casey, as well as Matt Fitzpatrick and Lee Westwood of England.
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His final pairing has an unconventional look, with Rory McIlroy's clean striking alongside Ryder Cup totem Ian Poulter.
"We knew our partnerships well in advance and you don't want to get bored playing with a guy," Harrington said of his choices, who have had just one practice together in partnership.
They did have a trial at foursomes but I just did not want them to overdo it.
"You want to turn up on Friday with a bit of freshness and excitement."
Foursomes is played with each team-mate taking alternate shots, with one player teeing off on the even holes and the other the odd nine.
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American captain Steve Stricker went largely route one with a set of widely-forecasted pairings.
Dustin Johnson's long-driving will marry with Open champion Collin Morikawa's sharp iron-play, while Brooks Koepka and Daniel Berger are near neighbours in Florida.
Patrick Cantlay and Tokyo 2020 gold medallist Xander Schauffele are California state-mates, too, and will hope to secure what could be a vital final morning encounter with McIlroy and Poulter.
"I feel great about our pairings," Stricker said after an opening ceremony of typical pomp and pageantry.
We are extremely excited about how these guys are playing, and the order in which they are going out.
Stricker has resisted the urge to unleash Bryson DeChambeau, whose unconventional style off the tee may not have coalesced with any potential partner.
Ryder Cup Foursomes (Friday 24 September)
Justin Thomas and Jordan Spieth (USA) vs Jon Rahm and Sergio Garcia (Europe) 1.05pm BST (7.05am local time)
Dustin Johnson and Collin Morikawa vs Paul Casey and Viktor Hovland 1.21pm BST
Brooks Koepka and Daniel Berger vs Lee Westwood and Matt Fitzpatrick 1.37pm BST
Patrick Cantlay and Xander Schauffele vs Rory McIlroy and Ian Poulter 1.53pm BST
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