With all eyes on Woods all week, McIlroy flew under the radar and entered the final round two shots back of Henrik Stenson. With what McIlroy did to finish, however, with five birdies in his last six holes, Woods was not going to catch the Northern Irishman anyways.
"I'm just so happy to be back in the winner's circle again and win a tournament that has Arnold Palmer's name on it, someone that means so much to us in the game of golf".
"Something clicked into place with my game and obviously something clicked into place in my putting and this is the result".
"I wasn't that far away", McIlroy said about his game, despite two missed cuts in four previous tour contests this year.More news: Syria's Assad visits Eastern Ghouta troops in rare 'front line' visit
Seven-time major victor Palmer died aged 87 on September 25, 2016 - just hours after McIlroy claimed the Tour Championship and the $US10 million ($A14 million) FedEx Cup series.
Briton Justin Rose (67) finished alone in third while Stenson (71) faded to fourth.
Eight-time victor Tiger Woods closed with a round of 69 to finish eight shots back, meanwhile, and Justin Rose was third thanks to his 67 on Sunday.
After a tense afternoon at Bay Hill Golf Club, McIlroy had looked poised for an uneventful finish when he stepped onto the 18th tee with a three-shot lead.
DeChambeau sank a 15-foot eagle putt to pull one stroke behind McIlroy only to have the European star sink a 25-footer for birdie, raising his arms in victory.
"Freed up my head more than my stroke", said McIlroy, who moved up to No. 7 in the world.More news: Frustrated Trump lashes out at special counsel Mueller
"The last time I won a PGA Tour event was the day Mr. Palmer passed away and so it's a little bit ironic I come here and win".
"Really proud of myself, how I hung in there over the past year, with injuries and taking a little bit of time off at the end of last year to sort of get myself right coming into this year and all that work, hard work has finally paid off".
"I'm starting to piece it together, tournament by tournament, and each tournament's gotten a little crisper and a little bit better", Woods told Gold Digest in Florida. I figured I had to play the last three holes in 3-under to have a chance of probably forcing a play-off.
"I felt like I really putted well the entire week (and) hit a lot of good putts", Woods said after finishing with four rounds of par or better.
The 14-time major champion, mired in the longest win drought of his career, has shown form in back-to-back weeks to excite fans for his chances at the Masters, which begins April 5.More news: Robert Mueller Subpoenas Trump Business For Russia, Other Documents
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