McIlroy also reserved words of praise for Fleetwood, who birdied six of his back nine to retain the trophy at Abu Dhabi Golf Club.
McIlroy made the turn in two under on Sunday but settled for pars on Nos.
Fleetwood, who is the current Order of Merit champion on the European Tour, showed his class with a superb second shot from the waste area while stymied behind a tree to six feet for birdie.
"You still have to hit a lot of good shots out there", Garcia said.
Indeed, his double-bogey at the par-4 15th after needing two shots to extricate himself from the sheer cliffs of the green side bunker was more indicative of Mickelson's struggles throughout the week.
Playing partner and European number one Fleetwood carded a flawless 66 to lead by a shot from Paraguay's Fabrizio Zanotti, with the final member of the marquee group, world number one Dustin Johnson, struggling to a 72.
1 had started the day 2 behind overnight leaders Fisher and Thomas Pieters.
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The US State Department had warned last week of a possible attack by extremist groups targeting Kabul hotels. Violence like what we witnessed yesterday has no place in Afghanistan or anywhere else in the world".
A delighted Fleetwood felt the win validated his position as Europe's No1 golfer.
"It was pretty good on that back nine really", said Fleetwood, whose win is set to take him into the top ten on the Official World Golf Ranking.
"I don't know if I've ever played better golf than that, but I do know that score was very, very good in those conditions". Difference is all in the putts.
"I holed the putts on the back nine, ten, 12, 13, 15, 16, the up-and-down on 18". It's felt like a while since I've won and just to give myself these chances; I gave myself a chance at the end of the year at Close House and wasn't able to do it.
"Last year, I had the year of my life by a long, long way on the course".
"It was important to come out and make sure I'm hungry. To sort of validate your position as the Player of the Year so early on is really satisfying in a way".
Still brimming with confidence after claiming his first major title at Augusta National past year, Garcia started his new season with a runaway victory at the Sentosa Golf Club, finishing at 14-under 270. "Tommy's gone out there and shot 65 and he's won it, so all credit to Tommy".
"[It was] very stress-free", Fleetwood said.