Rory McIlroy took all of the drama out of the U.S. Open with his wire-to-wire win, but he has plenty to fret about now.

McIlroy injured his right wrist in Thursday’s first round of the PGA Championship. He braved his way around Atlanta Athletic Club's Highlands Course for an even-par round of 70. He left for an area hospital for an MRI shortly after finishing. His playing status for Friday was pending the results of the test.

“If it’s the same tomorrow, and I know that I’m not going to do any more damage to it, I will play,” McIlroy said. “There were a couple of points where I thought about not continuing. It’s a very important tournament and I’m still even par and I’m still in the hunt. We’ll see what the results are ... and if I can strap it up and play again tomorrow I will.”

McIlroy was injured when he hit a tree root while swinging on the par-5 third hole. He immediately dropped the club and grabbed for his wrist. He experienced a sharp pain through his wrist, up his forearm, elbow and into his shoulder, and later swelling in his wrist. McIlroy said he didn’t think the root was close to his ball.

“I thought I could get away with it,” McIlroy said of the shot. “In hindsight, it would have been better to chip it out sideways and still make a five. It was a shot that I felt like, if I took it on and pulled it off, it might save me a shot.”

McIlroy iced the wrist for the next several holes and even birdied the fifth and sixth holes to move to 1-under par. After McIlroy had a three-putt bogey on No. 8, a doctor wrapped his thumb, wrist and forearm.

“They said it was your decision,” McIlroy said. “If you want to play on, and you feel comfortable to play on, then do that. If not, there is no point in risking it. It’s the last major of the year. I have six or seven months until the Masters. I might as well try to play through the pain.”

The injury seemed to affect McIlroy the most off the tee. On No. 10, he went way right and his ball dropped short after hitting a tree. He played down a fairway of AAC’s Riverside Course, which runs parallel to the 10th, hit the green with his approach shot and rolled in the putt for par. A huge roar from the gallery followed.

He drove it into the trees left of the No. 12 fairway, punched out, hit the green of the par-5 hole with this third shot and dropped a birdie putt. He couldn’t escape a wayward tee shot on the par-3 15th hole that landed in the greenside bunker. He bogeyed to drop back to even par. A three-foot birdie putt on No. 16 put McIlroy in red numbers again, but he gave it back with a three-putt bogey on No. 17.

McIlroy said he felt the most pain at impact of each shot. He often flexed his wrist throughout the round, aware he was less than his best.

“There were times when I finished with one hand and I hit some good shots,” McIlroy said.

Playing partner Darren Clarke provided a moment of levity while walking to the final tee box. Clarke’s caddie stepped on the back of his foot causing him to stumble. After a moment to collect himself, Clarke looked at McIlroy, smiled and said, "Doctor!"

“Right now it’s OK,” McIlroy said following the round. “It’s just throbbing a little bit in the swollen area.”