A foot infection could keep former champion Jon Rahm out of the 124th US Open.
Rahm withdrew from the LIV Golf League event in Houston during Saturday's second round because of an infection in his left foot and arrived for his pre-tournament press conference at Pinehurst wearing one shoe and one flip-flop.
"It's a concern," the 2021 winner said. "It's doing better. But definitely still in pain.
"Could I have dragged myself out there (on Saturday) and posted some kind of a score? Yeah.
"But it was getting to a point where I wasn't making the swings I wanted to make, and I could have hurt other parts of my swing just because of the pain. As to right now (playing) this week, I don't know."
Asked how he had suffered the injury, Rahm added: "We've been trying to figure it out because I think that the closest term would be a lesion on the skin. If I were to show you, it's a little hole in between my pinky toe and the next toe.
"I don't know how or what happened, but it got infected. The pain was high. On the Saturday round, Saturday morning, I did get a (painkilling) shot to numb the area.
"It was supposed to last the whole round and by my second hole I was in pain already.
"The infection was the worrisome part. The infection is now controlled, but there's still swelling and there's still pain.
"There's a reason I walked out here in a shoe and a flip-flop, trying to keep the area dry and trying to get that to heal as soon as possible.
"But I can only do what I can do. The human body can only work so fast."
Rahm will not play a practice round until Wednesday but can at least rely on his experience of playing the course a few weeks ago as he bids to improve on some poor results in this season's majors.
"I'm in a happy place," insisted the former world number one, who was 45th in the defence of his Masters title and missed the cut in the US PGA.
"It's not like I've been playing bad, even though a lot of you make it sound like I'm playing bad. I've had two bad weeks.
"I've been top 10 and had a chance to win in most of the tournaments I've played, and then unfortunately Augusta and PGA wasn't my best showings. But, yeah, I'm happy.
"I mean, it's been a wonderful career so far. And, yeah, it hasn't been the best first half of the year, but there's been many times where I haven't had a great start, but that doesn't mean you can't have a great finish."
