He was playing with Rickie Fowler, who also had a share of the lead in the morning. The victor in 2015 wants to add yet another to his resume.
This is the second ace on No. 17 in the last two years.
McIlroy wasn't exactly chopped liver in those seasons, of course, finishing with four top-10 finishes in the majors in 2015 and 2016 to go along with four total wins across all tournaments. I can't see him falling off.
No need explaining that to Adam Scott, who won The Players in 2004 and was off to a strong start on a steamy afternoon when he was 6 under and heading to the infamous par-3 17th with its island green.
Defending champion Jason Day, winless since his victory at The Players previous year, was 5 under through 11 holes until he dropped shots on three of his last four holes for a 70.
The pledge apparently doesn't extend to the golf course. World number one, Dustin Johnson has overcome the back injury which forced him out of Augusta in April having fallen down the stairs on the eve of the tournament. It kind of tests all parts of your game. "So it was a frustrating time in the round where I was trying to kind of get some momentum going". He felt nerves on the first tee when he was introduced as the Masters champion. Other changes were more cosmetic.
Phil Mickelson decided on a novel approach to this year's Players Championship after missing the cut the past four years.
The 28-year-old Fowler has won seven times since turning pro in 2009.
This year, as usual, we will see the cream of the crop in golfing circles compete for the championship. He also finished tied for third at the PGA Championship and fifth at The Masters. Rickie Fowler said he would like to be amongst the top players in the world.
"I would love to be in that position, continue to focus on the short-term and smaller goals to ultimately work my way there". That's going to happen. I went to tap one in, and it came straight left off the putter, and thought to myself, I'd better mark the next one.
Here's a look at the live 2017 Players Championship leaderboard with scores and results from Round 1 at TPC Sawgrass. He said he was pleased with how the round played out.
"It could have been really good today, but ended up just being OK", Johnson said. 11 of 14 fairways, 15 of 18 greens. Other than that, it was 16 really good golf holes. "My back has got a little bit stiff again, I guess just from obviously building it up and playing through and then not doing anything for three weeks and then coming back last weekend and hitting balls for four or five hours a day".
"No one's going insane low or anything like that", he said.