The natural ease with which he achieved his 2&1 victory over 2011 PGA champion Keegan Bradley was nothing like the high speed drive to Medinah compliments of an Illinois state trooper.
"I've never been so worried going to the golf course," the Northern Irishman said.
McIlroy, 23, thought his tee time was an hour later, confused by listings that showed his match against American Keegan Bradley was to start at 12:25 Eastern time, unaware that the Chicago area is on Central time which is one hour earlier.
The world number one was casually leaving his hotel when he got an urgent call from Medinah saying he was in danger of missing his tee time.
"Luckily there was a state trooper outside the lobby of the hotel that took me here and got me here a lot faster than we would have normally," the mop-topped McIlroy said.
"I had just enough time to put my shoes on, have a couple of putts and go to the first tee."
McIlroy, who wolfed down an energy bar as he took his practice putts, said his tardiness might have worked in his favour.
"In a way it wasn't a bad thing because I didn't have time to think about it, and I just went out and played, and I played probably the best I've played all week," he said.
"I still would have liked to have gotten here sooner, but I delivered my point for the team and that was the most important thing."
McIlroy's point helped Europe overcome a 10-6 deficit to the United States on the way to a victory that matched the greatest Ryder Cup comeback ever.
Had he taken much longer to arrive at Medinah, Europe and McIlroy might not have had a win to celebrate since Europe's margin of victory was just one point.
"There's nothing better than celebrating a win with your team-mates," said McIlroy.
"It is the most special and unique golf tournament we have, period."
- Keegan Bradley