World number one Rory McIlroy has revealed that he had to abandon the Honda Classic midway through the second round with wisdom tooth pain.

The Northern Irishman shocked spectators when he walked off the course without completing his ninth hole after dropping seven shots on the second day of play in Florida.

While reports had claimed that the 23-year-old admitted to not feeling 'mentally right', McIlroy has blamed a "sore" wisdom tooth for his exit.

"I sincerely apolgise to the Honda Classic and the PGA Tour for my sudden withdrawal," Sky Sports News quotes McIlroy as saying. "I have been suffering with a sore wisdom tooth, which is due to come out in the near future.

"It began bothering me again last night so I relieved it with pain killers. It was very painful this morning and I was simply unable to concentrate."

McIlroy won the tournament last year.