Rory McIlroy Reinhold Matay-USA TODAY Sports

During the first round of the RBC Canadian Open on Thursday, PGA Tour superstar Rory McIlroy had a bit of a slow start in the first half of his round, making nine straight pars to start his round. And it sounds like there may have been a pretty good reason why McIlroy was not dominant right off the bat – he was out drinking the night before.

During his press conference following the first round, Rory McIlroy revealed that he went out the night before for a birthday dinner for his caddie Harry Diamond. At the dinner, McIlroy had “a couple of glasses of win” which he says contributed to his slow start on the day.

“A bit of a slow start,” McIlroy admitted according to Golf Week. “Harry’s birthday dinner last night so had a couple of glasses of wine. I was probably feeling a little groggy when I woke up.”

That would make sense, given that McIlroy had a 7:40 a.m. tee time. After a night of drinking, a tee time that early does not always lead to the best golf.

But McIlroy was able to bounce back from the slow start, finishing with four birdies in the second half of his round to bring his score to a 66.

Still, it’s pretty hilarious to hear a professional golfer admit to being a little hungover on the course.

[Golf Week]