Rory McIlroy's quest for a fifth major title at this week's PGA Championship just got a little more uncomfortable—and it's not because of the pressure. The four-time major winner is nursing a lingering foot blister that's already become a hot topic ahead of Thursday's opening round.

During a practice round at Aronimink Golf Club on Tuesday, McIlroy was spotted repeatedly removing his shoe, a clear sign of discomfort. The issue first surfaced after the final round of last week's Truist Championship at Quail Hollow, where McIlroy revealed the source of his irritation.

"I've got a blister on my pinky toe on my right foot," McIlroy explained after his round in Charlotte. "But it's underneath my nail. So I can't really get to it or so it's a little sore, but I'll be all right."

The timing is less than ideal. McIlroy cut his Tuesday practice session short after just a few holes, according to ESPN's Paolo Uggetti, raising questions about whether the blister will impact his performance at one of golf's biggest events.

In a twist of cruel irony, McIlroy is scheduled to play alongside Jon Rahm on Thursday and Friday. Two years ago, the Spaniard was forced to withdraw from the U.S. Open due to a foot injury—a reminder that even the smallest physical setbacks can derail a major championship campaign.

With extra rest and treatment, McIlroy should be ready to go by Wednesday's final tune-up or Thursday's opening round. He's slated to tee off from No. 10 at 8:40 a.m. ET, hoping his pinky toe—and his game—hold up under the spotlight.