Ruthless Europe dominate USA after foursome sweep at Ryder Cup
Viktor Hovland set the tone with a chip-in on the first hole, while Jon Rahm and Tyrrell Hatton clinched the first point with a dominant 4 and 3 win over world number one Scottie Scheffler and Sam Burns.
McIlroy hit a brilliant tee shot to close out a tense 2 and 1 win with Tommy Fleetwood in the final match against Xander Schauffele and Patrick Cantlay.
The USA never led in any of the four matches, in a nightmare start to their bid to win on European soil for the first time since 1993.
European captain Luke Donald had opted to switch the usual schedule and open with the alternate shot foursomes instead of fourballs in the hope of a "fast start" which his team delivered in style.
"It's been an unbelievable session," said McIlroy. "We switched the format this year to go foursomes first because statistically that's our better session."
Europe are aiming to regain the trophy after suffering a record-breaking 19-9 thrashing by the Americans at Whistling Straits two years ago.
US skipper Zach Johnson responded to the morning mauling by naming Ryder Cup stars Jordan Spieth and Justin Thomas, who he had surprisingly left out for the foursomes, as his opening afternoon fourballs duo.
They will face Hovland and Hatton, while Brooks Koepka will also take to the course for the first time alongside Scheffler, facing Rahm and Nicolai Hojgaard.
All 12 players from both teams will feature on the first day.
"I'm not worried. Our team is deep. These boys will come out hungry these next matches," said Schauffele.
Rahm leads from front
Masters champion Rahm was Europe's talisman early on, curling in a birdie putt from the fringe to put himself and Hatton ahead on the third hole as the late autumn heat set in for the day.
He also chipped in for par on the 10th hole and then drove the green on the par-four 11th as the European pair turned the screw.
Rahm's biggest highlight was a near hole-in-one on the par-three seventh, with his tee shot hitting the pin but just staying out.
"I think it might have been too much if it goes in but it got the job done," said Rahm.
Norwegian Hovland and Swedish sensation Ludvig Aberg, who is the first golfer to be selected for a Ryder Cup without playing in a major championship, cruised to another 4 and 3 victory against Max Homa and Brian Harman.
Shane Lowry and Sepp Straka rode the wave with a 2 and 1 success over Collin Morikawa and Rickie Fowler.
Schauffele and Cantlay, the most tried and tested US pairing in the absence of Spieth and Thomas, put up more of a fight in the bottom match against McIlroy and Fleetwood.
But the home pair inflicted Schauffele and Cantlay's first foursomes defeat in international competition after five previous successive wins.
The Americans appeared set to level the match with three holes to play, but Fleetwood poured in a 25-foot par putt and then Schauffele missed a short effort of his own to leave Europe 2-up instead.
The US pair fought back to one-down but McIlroy closed out the match in style by drilling his iron shot on the par-three 17th within two feet of the pin.
USA desperate for turnaround
The USA will now be hoping to emulate Europe's women, who lost the first session of last week's Solheim Cup 4-0 before fighting back for a 14-14 tie to retain the trophy.
Johnson needs a quick response to fight back the European tide and he will be hoping Spieth, Thomas, Koepka and US Open winner Wyndham Clark can provide the spark.
Five-time major champion Koepka is the only player from the Saudi-backed breakaway tour LIV Golf on either team after he won the PGA Championship in May.
Veteran Justin Rose admitted the Europe team might be "in transition", but rookies Straka and Aberg were up to the task in the morning.
Donald will be expecting Robert MacIntyre, playing with Rose against Homa and Clark, and Hojgaard to also perform in their debut matches.
