Rory McIlroy showed great fighting spirit to battle through a worrying back injury that threatened to end his hopes of defending his FedEx Cup title, saying he was "over the moon" to just be three shots off the lead after the first round of the Tour Championship.
McIlroy said he couldn't event address the ball on Wednesday due to a back spasm, and was in visible discomfort as he tried to go through his pre-round warm-up at East Lake on Thursday.
And despite some tentative looking swings and a slow start, the four-time Major champion recovered to card a level-par round of 70 to sit just three shots off joint-leaders Viktor Hovland, Collin Morikawa and Keegan Bradley.
"I honestly couldn't address the ball this time yesterday," McIlroy said in his post-round interview with reporters. "So to get to where I am today is good.
"I hung in there and I just felt like if I could get through today, it's better than it was yesterday, hopefully tomorrow's better than it was today, and just sort of try to keep progressing.
"So the fact that I'm only going to be - whatever it's going to be, like, three or four off the lead, I'm over the moon about."
McIlroy said he was always going to start the Tour Championship at East Lake in Atlanta and try and get through the round - hoping the back will improve day-to-day.
"So I got here really early this morning, like 7:45, so like six hours before my tee time, did cold tub, did everything," McIlroy explained. "I hit 20 wedges by 10am which is the first balls I've hit since Chicago. I felt okay, so then just thought I would give it a go.
"So I was always going to tee off. It was just a matter of how I felt on the course. And it got progressively a little tighter as I went, but it will hopefully get loosened up here and just another 20 or 18 hours of recovery and go again tomorrow."
Rory McIlroy working through the discomfort on the range @TOURChamp. pic.twitter.com/raeImLEotfAugust 24, 2023
McIlroy had a physio walking the course with him during the first round in case his back seized up again, while he was stretching it during the day and caddie Harry Diamond also helped out with some treatment.
It's a common problem for McIlroy to suffer with tightness down his right side, but he detailed how this time it went a step further.
"I think when I play a lot of golf, especially the end of the season, I always have to manage my right side. My right side always gets pretty tight, my rib cage, intercostals, lats, like, all the way down, right hip.
"On Tuesday morning I felt a little tight, and I went into my gym at home, and I just sort of foam-rolled and stretched. I went to grab something and my whole right side just completely seized up, spasm.
"So I spent two hours with the physio at home, flew up here, felt a little better, some treatment, then Wednesday morning still my right side was feeling better, and then went into the gym just to do some movements and stuff.
"I was at the bottom of a squat, a body-weight squat, and my whole lower back spasmed, seized up.
"A muscle spasm that's being protective of, you know, like my ribs, joints, everything. So, but it's, look, the muscle spasm is what's giving me the discomfort."