The Masters champion had his regular driver deemed non-conforming Tuesday and had to put a backup in play at Quail Hollow.

Rory McIlroy had to switch drivers at the PGA Championship after his gamer was deemed non-conforming, according to a report by SiriusXM PGA Tour Radio’s Jason Sobel. McIlroy is known as the best driver of the golf ball of his generation.

There is precedent for what Rory McIlroy will need to do at the PGA Championship to win, but he is not going to like what that is.