McIlroy had just rolled in an eagle putt from 15 feet to restore his five-stroke lead at Royal Liverpool.
For Garcia, another shot at a first major title was slipping by.
''I've always said, at the end of the day we're all doing our best,'' Garcia said. ''And if somebody is better than you, you can't ask yourself for anything else.''
Problem is, Garcia's best hasn't quite been good enough at the majors.
Since missing the cut as an amateur at the British Open in 1996, he has recorded nine top-five finishes in the majors. One of them came here in Hoylake in 2006, when he was tied for fifth after shooting a final-round 73 when in the last pairing with Tiger Woods.
On that occasion, he had been one stroke off Woods' lead after three rounds. Eight years on, his task is even harder - McIlroy is seven shots ahead of him.
''If Rory plays the way he's been playing, it's difficult to see anybody catching him,'' Garcia said. ''But the only thing I can do is play well, try to put a little pressure on him, and see how he reacts to that.''
The 34-year-old Garcia was once the Boy Wonder like McIlroy, a player who people were predicting would win several majors and provide a regular challenge to Woods in golf's biggest tournaments.
It hasn't worked out that way - after a final-round collapse at the Masters in 2012, he wrote off his chances of ever ending the major drought - and much of the blame can be attached to his putting.
Two three-putts in the first three holes saw him drift away from contention on that final day in 2006, and the putter let him down here on Saturday on the back nine.
After picking up four shots from Nos. 2 to 9, Garcia was three shots behind McIlroy and on a roll with playing partner Rickie Fowler.
He kept giving himself birdie chances but couldn't convert, notably at No. 12 where he missed a short putt. Garcia two-putted for birdie at No. 16, but was in the rough beside the 17th green when McIlroy made his big move.
''Obviously I heard the roar on 16,'' Garcia said. ''I imagined it was an eagle.''
In largely wind-free conditions, the 18th was playing easy but Garcia tugged his tee shot left, pushed his second shot right, and left himself a 20-foot putt for birdie. He missed.
''The only thing I would have loved to (do) is hit a couple of better shots coming in on (Nos.) 17 and 18,'' Garcia said. ''That was what disappointed me a little bit more than seeing Rory making eagles and birdies.''
Garcia won't be without support in the final round. The galleries at Royal Liverpool really got behind him in 2006 when he was dressed head to toe in garish yellow but Woods was too strong a foe.
This time, it's McIlroy who'll likely deny Garcia the claret jug.