Report: Rory McIlroy involved in equipment controversy before PGA Championship

USGA officials reportedly told Rory McIlroy the 'gamer' driver he had in the bag for the PGA Championship was non-conforming. 

According to SiriusXM PGA Tour Radio, the newly-crowned Masters champion was forced to change the driver he planned to use before the first round of the second men's major of the year. 

The reason why it was deemed non-conforming was not initially made clear. 

Unsubstantiated reports have suggested the club failed a CT (characteristic time) test. 

CT tests are used to used to evaluate how much a clubface (usually a driver, but sometimes fairway woods and hybrids) flexes or 'springs' when it makes contact with the ball.

McIlroy struggled on day one of the major championship at Quail Hollow Club in North Carolina, only finding four fairways on his way to a 3-over 74.

He battled hard to make the cut on the number on day two. 

McIlroy is currently using TaylorMade's Qi10 driver. In March, he switched to the latest Qi35 fairway woods for the Arnold Palmer Invitational at Bay Hill. 

But he decided to switch back after only 36 holes of the signature PGA Tour event and paid $995 for an Uber driver to deliver his old clubs from his residence in Jupiter, Florida. 

At the time of publication, there has been no official announcement by the PGA of America or the USGA. 

The radio station later confirmed both the PGA of America and the USGA declined to comment.

The USGA cited the fact that testing results are confidential.

McIlroy ranked 85th in terms of strokes gained: off the tee and 41st in driving distance on Thursday, well down on his PGA Tour average, which is first and third over those metrics.

Johnson Wagner defends Rory McIlroy

Former PGA Tour pro turned pundit Johnson Wagner defended Rory McIlroy after the news broke. 

Wagner said: "So the USGA conducts these tests pretty much every week and they test it across aspects of the face of the driver. 

"Drivers fail all the time. Every single week somebody's driver fails. It is of no fault of the player, they don't know how to do it [the test]. It is a sophisticated testing system.

"And when you are player like Rory McIlroy that hits the ball as hard as he does the face naturally thins out.

"When you hitting it like Rory McIlroy with his speed it thins out a little quicker and it's unfortunate that it happened the week of a major and it maybe cost him a few shots yesterday but he seems to have it figured out today.

"He did nothing wrong. No player [whose driver fails the test] ever does anything wrong. This is something that happens week to week on the PGA Tour."

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