Rory McIlroy opened the PGA Championship with a steady, if unspectacular, round at Aronimink on Thursday, but his performance may be overshadowed by a potential rules controversy. The 37-year-old Northern Irishman has been battling a painful blister on his pinky toe, an injury he picked up at the Truist Championship last week. This forced him to cut short his practice round ahead of the major, though he showed no signs of limping during the first day of play.

Despite being physically fit, McIlroy's game looked rusty. He managed to stay even-par through 14 holes, but a couple of sloppy bogeys hinted at his struggles. However, it was an incident on the fourth tee—his 13th hole of the day—that caught the attention of golf analyst Paul McGinley. After flaring his tee shot into the thick rough on the right, McIlroy slammed his driver into the turf in frustration.

McGinley expressed concern that this outburst might violate the new code of conduct rules implemented at the start of 2026 for all major championships. "There's a new code of conduct that has come in for all the major championships now. We saw it at The Masters. I don't know if that's considered a breach or not," McGinley said.

The new rules were introduced in response to a wave of poor behavior on the course during the 2025 season, with players like McIlroy, Shane Lowry, and Cam Young all guilty of angry outbursts. The USGA has confirmed the stricter code, aiming to clean up the sport's image. While McIlroy's actions on the fourth tee were certainly not pretty, penalizing him with strokes would be a harsh call—especially compared to the more egregious incidents we've seen this season, such as Sergio Garcia's meltdown at The Masters last month.

For now, McIlroy will need to keep his cool as he looks to climb the leaderboard. Whether his driver slam becomes a footnote or a costly mistake remains to be seen.