Collin Morikawa has built his reputation on precision and trust in his swing. But as he heads into the PGA Championship, the two-time major winner admits he's facing an unfamiliar opponent: his own body.

Since injuring his back on the second hole of the Players Championship last month, Morikawa has been battling what he calls "trust issues" every time he steps up to the ball. It's a challenge that haunted him at the Masters and continues to linger as he prepares for the 108th PGA Championship at Aronimink.

"I wish I was 100 percent healthy," Morikawa said during his pre-tournament press conference. "The body doesn't feel bad, just it's uncomfortable."

In golf, "uncomfortable" is a dangerous word. At a major championship, it can feel like being stranded on an island. Yet somehow, Morikawa has managed to grind through. He posted a T-7 finish at Augusta National last month and followed it with a T-4 at Hilton Head the following week. Those results would be impressive for any player, let alone one dealing with a nagging injury.

But statistics don't tell the full story. For Morikawa, the mental battle has been just as intense as the physical one.

"I've never had to deal with it," he said. "I can't imagine wanting anyone to deal with it because it's just a very weird feeling of not trusting the body and yet knowing that things are going to be okay. So it's just taking it day by day, doing what I need to do."

The 2020 PGA champion has had to completely rethink his approach over the past month. Gone is the freedom of a full, unrestrained swing. Instead, he's learning to compete with a cautious mindset—a challenge that would test even the steadiest of players.

While he struggled at the Cadillac Championship, his season overall has been a success. But what Morikawa seems most proud of isn't the leaderboard—it's how he's handled the mental strain when trusting himself felt impossible.

"I've got great physios at home, I've got a great physio on the road," he said. "Rick Sessinghaus and I have been working for quite some time and talking about the mental game and finding ways to feel comfortable out there. He's a big, big proponent and component of me being able to compete."

As the PGA Championship tees off, all eyes will be on Morikawa—not just for his game, but for how he manages the delicate dance between mind, body, and the trust that holds them together.