On a day with plenty of headliners injecting the 2018 Arnold Palmer Invitational with palpable enthusiasm and "Are you believing this?!" looks, Rory McIlroy took center stage down the stretch and put the accelerator down with a closing 8-under 64 and his first PGA Tour victory since the 2016 Tour Championship.

McIlroy went out in 33, and the top of the leaderboard was rich with major winners. McIlroy joined Henrik Stenson and Justin Rose around the lead halfway through the day with Tiger Woods charging in the distance. With the tournament outcome hanging in the balance and Woods trying to take it by the throat, it was McIlroy who birdied five of the last six holes to get to 18 under and beat Bryson DeChambeau by three.

He did it every way possible, too. McIlroy chipped in, buried long putts, hit 375-yard drives and then he closed like champs close: with a hammer and a roar.

"I've seen Tiger make this putt enough times, I know what it does," McIlroy told Steve Sands of NBC. "I wanted to try and emulate that. I didn't quite give it the hat toss. I was thinking about doing it. To be able to create my own little bit of history on the 18th green here is pretty special. I'm really proud of myself to have hung in there over the past ... nearly a year with injury and everything else that's happened. It feels really nice."

It had been a mildly bumpy ride for McIlroy, who didn't have a top 10 on the PGA Tour this season and came into the week outside the top 120 in strokes gained on approach shots as well as putting. He also came in off a missed cut at the Valspar Championship last week. None of that mattered with the chips down on Sunday afternoon at Bay Hill and the world watching to see what Tiger (and friends) would do.

"I worked on my swing, my ball-striking, my iron play," McIlroy, who had a putting chat with Brad Faxon recently, told Sands. "I kept saying it the last few weeks, I wasn't that far away. It just takes something to click into place. Something clicked into place with my long game. Obviously something clicked into place with my putting as well, and this is the result. It's so nice to see everything come together finally."

McIlroy gained 10 strokes on the field this week with his putter and finished first in that category. It's the best putting week he's ever had on the PGA Tour. And it came at the perfect time. With Augusta National and McIlroy's shot at the career slam on deck, he needed something good to take into the first major of 2018, and he got it. 

He also got some sweet symmetry from his last win in September 2016.

"To be able to win his event, I wish I walked up that hill and got a handshake from him," said McIlroy of Palmer. But I'm so happy to put my name on that trophy." Grade: A+

Here are our grades for the 2018 Arnold Palmer Invitational.

Justin Rose (3rd): He's now finished in the top 10 in 13 of his last 15 events worldwide. Even more remarkably than that, Rose was 4 over through six holes on Thursday in Round 1 here. That means he played his final 68 holes in 18 (!) under. Related: As my pal Andy Johnson at The Fried Egg pointed out, because of the way Bay Hill is set up, you get iron-hitting savants like Rose and Co. in the mix seemingly every year. The Englishman will now take a pretty outstanding run of golf into Augusta National in a few weeks, where he'll combine it with three straight top 10s including two runners up. Grade: A

Henrik Stenson (4th): Poor Stenson just got run over by an amped-up McIlroy. He played fine on the weekend (2 under overall), but McIlroy putted as well as he's ever putted in a PGA Tour event (literally). It's tough sledding to play 72 holes, make just six bogeys and get buried in the end, but there was nothing Stenson could do. However, he finished with his sixth top 15 in the last seven years at Bay Hill. All the paychecks. Grade: A

Tiger Woods (T5): He was fabulous before fading with a bogey-bogey-par finish. Every facet of the game except for the driver is in tremendous shape. He finished in the top 20 in strokes gained on approach shots, around the greens and with the putter. Even an average week with the driver could have yielded a victory. It's Woods' first back-to-back top-five finishes since the 2013 Masters and Player Championship. Grade: A

Rickie Fowler (T14): Fowler contended for a while on Saturday before fading with a double bogey at the final hole in Round 3 and 74 on Sunday. However, he noted earlier in the week that the outcome at Bay Hill wouldn't affect how he felt about the week as a whole. Fowler served as one of the tournament hosts and took home the Philanthropy Award presented by the Arnie's Army Charitable Foundation.

"It's been fun being able to be here and represent Arnie and be one of the hosts," said Fowler. "I would say at the end of the day golf is kind of the main priority, and obviously trying to get the game going and that's a big part of why we're all here. I would say receiving the award on Wednesday, that's definitely the highlight of the week I think regardless of how we play. Receiving that award from the family, being recognized as the family seeing me as someone they see a lot of Arnie in, it's hard to describe what that means. So to get that and see the response from everyone, that's been pretty cool." Grade: B+

Jason Day (T22): The Australian struggled early on with a 73-71 start and didn't putt it the way he's been doing so all season. Day, the No. 1 putter on the PGA Tour coming into the week, finished 19th in the field. Still, he can take away the positive of a 67 on Saturday into the next few weeks as well as the Masters in three weeks. Grade: B+

The rest of our notes on the final day are below. If you are unable to view the analysis and highlights below, please click here.

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