Rory McIlroy reportedly had to switch drivers at the PGA Championship after his primary driver was ruled non-conforming to rules

Charlotte (AFP) - Rory McIlroy was forced to switch drivers at the PGA Championship after his regular driver was found to be non-conforming to rules in a test at Quail Hollow, according to a radio report.

Sirius XM PGA Tour Radio reported that second-ranked McIlroy, who won the Masters last month to complete a career Grand Slam, had to make the change after US Golf Association (USGA) found Tuesday that his driver was non-compliant.

McIlroy leads the PGA Tour in strokes gained through driving but was last in driving accuracy among 74 players who made the cut to play the weekend. He found only 10 fairways in the first two rounds.

Test results on clubs are kept private. They involve the flexibility of the face of a driver.

Drivers have been found to be conforming to the rules one week and fail a test the next due to general use of the club.

McIlroy has declined to speak with reporters after each of the first two rounds at Quail Hollow, a course where he has won four times in PGA Tour events.

Kerry Haigh, the PGA of America chief championships officer, would only confirm in a statement the USGA was asked to test clubs at the PGA.

“We can confirm that the USGA was invited to do club testing at the PGA Championship, at the PGA of America’s request,” Haigh said.

“That testing program is consistent with the same level of support that the USGA provides to the PGA Tour and other championships, as part of their regular programs for driver testing.”

Haigh said not every player has club’s tested every week.

“The standard process is for about a third of the field to be randomly tested under the program. That was the case at Quail Hollow this week,” he said.

“Finding driver heads that have crept over the line of conformance is not an unusual occurrence, especially for clubs that are hit thousands of times over a long period of time. The results are kept confidential to protect players, who are unaware the club has fallen out of conformance and not responsible for it falling out of conformance other than hitting the club thousands of times.”

Haigh said players are generally asked to change club heads and said “all do without issue” while noting why results are kept confidential.

“To publicly identify players whose club did not conform can lead to that player being questioned unnecessarily,” Haigh said.

“Neither the USGA nor the PGA of America have any concerns about player intent.”