Rory McIlroy is back on the greens at Aronimink, putting to rest any concerns about a blister that cut short his practice session on the eve of the PGA Championship. The world number two from Northern Ireland, fresh off his second consecutive Masters victory last month, is among the top favorites this week—but a nagging foot issue had fans worried.

On Tuesday, McIlroy limped through just three holes before stopping to treat a blister under his smallest right toenail. He removed his right sock and shoe, then took a cart back to the clubhouse. The blister had been bothering him since Friday, as he noted after his final round at a PGA Tour event in Quail Hollow on Sunday. In a proactive move, McIlroy told the Golf Channel he removed the toenail on Monday to better manage the irritation.

But by Wednesday morning, the four-time major champion was back in action. He started with a session on the practice area, then joined Ireland's Padraig Harrington and Shane Lowry on the 10th tee for a full practice round—showing no signs of discomfort. McIlroy had also tried on several pairs of shoes at the clubhouse on Tuesday to ease the pressure on his toe.

Now, with the blister behind him, McIlroy faces the challenge of Aronimink's 7,394-yard, par-70 layout over the next four days as he chases his seventh career major title. He's set to tee off Thursday at 8:40 a.m. (1240 GMT) alongside Spain's Jon Rahm and American Jordan Spieth—a star-studded group that promises early drama.

The stakes are high: no player has won both the Masters and PGA Championship in the same year since Jack Nicklaus in 1975. Meanwhile, Americans have dominated the PGA Championship, winning the last 10 editions and 10 of the past 12 majors—interrupted only by McIlroy's two Masters titles. Top-ranked defending champion Scottie Scheffler and McIlroy have combined to win four of the last five majors, with Scheffler posting top-10 finishes in each of his past six—the longest such streak since Vijay Singh's seven in a row ended in 2006.

Rahm, on track for a third consecutive LIV Golf season crown, is aiming to become the first Spaniard to win the PGA Championship, completing a "Spanish Grand Slam" of all four majors for his homeland. With so much on the line, McIlroy's toe—and his resolve—will be tested over the next four days.