Europe roar back into contention after a slow start
Fired-up McIlroy closes the gap for Clarke's troops with a stunning round as America is made to sweat
Darren Clarke said he was proud of his men after Europe fought back against Team USA to rekindle their hopes of winning a fourth consecutive Ryder Cup.
The hosts stormed into a 4-0 advantage after the opening session but Clarke's boys showed their true colours and character in the afternoon fourballs to only trail 5-3.
Olympic gold medallist Justin Rose and Open champion Henrik Stenson beat Jordan Spieth and Patrick Reed 5&4 while Sergio Garcia and Rafa Cabrera-Bello overcame JB Holmes and Ryan Moore 3&2.
Brandt Snedeker and Brooks Koepka notched USA's only point of the afternoon session with a 5&4 win over Martin Kaymer and the much-maligned Danny Willett, before Rory McIlroy and Thomas Pieters rounded the day's play off with a 3&2 victory over Dustin Johnson and Matt Kuchar.
Clarke said: "We were very disappointed at lunchtime, I'm not going to lie but they just didn't play the way we know they can.
"In saying that, America did and that's the beauty of matchplay golf. For us to come back in the afternoon and play like that was special, the golf was scintillating and I could not be prouder of those guys, they gave it everything."
McIlroy said he was thrilled to silence the hostile home crowd.
"It's pretty hostile out there, You don't want to let that get to you but you want to let them know when you hole a putt what it means to you," said the world number three.
"We were trying to keep the pressure on but I gave Thomas a lot to do in the middle of the round. A lot of credit to this guy. He's taken to the Ryder Cup so naturally.
Pieters added: "It's unbelievable playing with Rory. When I got into trouble he played some great shots."
Rafa Cabrera-Bello said: "It's been a real honour to play today and alongside Sergio was extremely special. I'm proud that we played great. We felt very comfortable on the course and we rooted for one another."
Fellow Spaniard Sergio Garcia said: "It was important because we didn't have a good morning. We needed to go out and do something better."
Earlier, the United States whitewashed Europe in the opening foursomes to take a 4-0 lead on the first day.
Jordan Spieth and Patrick Reed set the tone by beating Justin Rose and Henrik Stenson 3&2 in the top match.
Sergio Garcia and Martin Kaymer lost 4&2 to Zach Johnson, while Lee Westwood and Thomas Pieters were thrashed 5&4 by Dustin Johnson and Matt Kuchar.
Phil Mickelson and Rickie Fowler beat Rory McIlroy and Andy Sullivan one up to seal the first US sweep since 1981.
Europe had not been ahead after a first session since 2006, in which time they have won three of the four Ryder Cups.
But the scale of the US domination on the opening morning meant Darren Clarke's team had to pull off an incredible turnaround, even with 24 points still on offer, to defend the trophy and seal a fourth successive triumph.
Indeed, Davis Love's home team made 19 birdies to Europe's eight in front of a baying, partisan crowd.
Jordan Spieth and Patrick Reed got off to a flier in the opening match. In front of a raucous crowd Reed's birdie on the 16th then sealed the win and he said: "I live for those kind of moments, having the whole crowd behind me gets me going. It was an awesome feeling."
Clarke was stung by the 4-0 scoreline but asked if his fourball pairings had been impacted by the morning's action, the Ulsterman, who left Chris Wood and Matt Fitzpatrick on the sidelines, added: "No, they weren't really affected. It was intended to get Danny (Willett) and Rafa (Cabrera-Bello) out there and get the rookies in.
"Fourballs is a totally different format to the foursomes."