WATCH: 'That's unbelievable' - Rory McIlroy produces moment of magic as Europe storm into Ryder Cup lead
Europe whitewashed the United States in foursomes for the first time in Ryder Cup history to turn the 42nd biennial contest on its head in Paris.
Trailing 3-1 after the morning fourballs, home captain Thomas Bjorn kept faith with his planned afternoon pairings - including a desperately out-of-sorts Rory McIlroy - and was rewarded with a remarkable rout at Le Golf National.
McIlroy redeemed himself with a brilliant foursomes display alongside Ian Poulter as Europe overhauled a two-point deficit to roar into a 5-3 lead.
McIlroy and Poulter were paired together in match two and after falling two holes behind early on, they rallied to win out 4&2 against the USA duo of Bubba Watson and Webb Simpson.
The European pair were two up but looked to be in trouble on the 13th when Poulter put his partner into the rough at the edge of the water.
McIlroy faced a daunting approach shot, down slope and in thick rough, but produced one of the shots of the day to not only find the green, but give Poulter a birdie chance which he duly took.
That gave McIlroy and Poulter a three-hole advantage going up the 14th.
Justin Rose and Henrik Stenson set the tone with a 3&2 victory over Dustin Johnson and Rickie Fowler before McIlroy, who was the only player in the fourballs not to make a single birdie, partnered Ian Poulter to a 4&2 win over Bubba Watson and Webb Simpson.
Match three looked set to finish in record fashion when controversial wild card Sergio Garcia and rookie Alex Noren raced seven up on Phil Mickelson and Bryson DeChambeau after just nine holes, but the European pair eventually had to settle for a 5&4 success.
And Tommy Fleetwood and Francesco Molinari were soon celebrating a second win of the day, on the first birthday of Fleetwood's son Frankie for good measure, by defeating Justin Thomas and Jordan Spieth by the same scoreline.
The only previous sessions Europe had won 4-0 were both in fourballs, on the opening afternoon at Muirfield Village in 1987 and at The Belfry two years later.
"We believe in it as a group," Bjorn said after ending the day with a 5-3 lead. "There's a few guys sitting out who you would normally see in the first session but they were very keen to play this afternoon and prove we are a team and we did it with all 12.
"That was the plan through the whole week, we wanted to get everyone on the course today. It was a wonderful afternoon after a disappointing morning but there is a long way to go."
McIlroy added: "I think a big thing for us this week is resilience and persistence. You have to persist until it turns around for you. This morning wasn't ideal but it was still a better start than Hazeltine."
That was a reference to the whitewash Europe suffered in the opening session in 2016 and such a nightmare start was on the cards again until some late heroics from Molinari and Fleetwood, who birdied five of the last seven holes to beat Tiger Woods and Patrick Reed 3&1.
McIlroy and Thorbjorn Olesen had won just one hole in a 4&2 loss to Johnson and Fowler, while Rose and Jon Rahm twice enjoyed a two-shot lead over Brooks Koepka and Tony Finau in the opening match but eventually lost on the 18th.
Paul Casey and Tyrrell Hatton fell three down to Jordan Spieth and Justin Thomas when Spieth made five birdies in the first seven holes, but the English pair fought back superbly to get back on level terms after 13 holes, only for Thomas to crucially birdie the 15th and hold on for victory.
Molinari and Fleetwood were also in danger of suffering defeat when they lost three holes to par on the front nine to trail by two with eight to play, but Molinari birdied the 11th and 12th, Fleetwood repeated the feat on the 15th and 16th and Molinari finished it in style with another birdie on 17.