Updated

World No. 1 Rory McIlroy withdrew from The Honda Classic on Friday after a difficult eight-plus holes.

The defending champion had a pair of bogeys, a double-bogey and a triple-bogey in his first eight holes Friday morning at PGA National.

McIlroy started his second round on the back nine Friday. He narrowly missed the water with his approach at No. 11, then ran his chip through the green. That led to a double-bogey.

A poor drive at the 13th led to a bogey. McIlroy dumped two balls in the water at the 16th. He walked off with a triple-bogey and was 6-over through seven holes. McIlroy 3-putted for another bogey from over 40 feet out at No. 17.

On the par-5 18th, he dumped his approach in the water. McIlroy took a drop and hit another ball, then walked off.

"I sincerely apologize to The Honda Classic and PGA Tour for my sudden withdrawal. I have been suffering with a sore wisdom tooth, which is due to come out in the near future," McIlroy said in a statement. "It began bothering me again last night, so I relieved it with Advil. It was very painful again this morning, and I was simply unable to concentrate. It was really bothering me and had begun to affect my playing partners. I came here with every intention of defending my Honda Classic title. Even though my results haven't revealed it, I really felt like I was rounding a corner. This is one of my favorite tournaments of the year and I regret having to make the decision to withdraw, but it was one I had to make."

It has been a tough start to the year for the top-ranked player in the world. He switched to Nike clubs in the offseason and has yet to break par this season.

He started with a pair of 75s in Abu Dhabi, a European Tour event, and missed the cut. He didn't play again until last week, where, as the No. 1 overall seed, he dropped his first match, 1-down to Shane Lowry.

McIlroy mixed two birdies and two bogeys in his opening-round 70. He was 7- over par for his second round when he withdrew, and at least six strokes over the projected cut.

He is slated to play next week at the WGC - Cadillac Championship.