Rory McIlroy’s bid for back-to-back major glory suffered a major blow on Thursday.The two-time Masters Champion finished four over-par in the first round of the PGA Championship.GettyMcIlroy finished his first PGA Championship round four over-par[/caption]He was never able to find his footing at Aronimik Golf Club, managing just two birdies and six bogeys total.McIlroy unravelled with five bogeys on his back nine, including four in a row to finish his round to fall away from the clubhouse lead which stands at three under par.When asked to describe his opening round, the 37-year-old delivered one simple word as a response.“S***,” McIlroy said, via GOLF.com’s Sean Zak.“I started missing fairways and from there it’s hard. I didn’t have great angles – and then I got on that bogey train at the end.“I’m not driving the ball well enough to give myself scoring opportunities and that’s pretty frustrating, especially when I pride myself on driving the ball.“There is certainly a penalty for missing the fairway and it’s probably more than what I anticipated.”Paul McGinley gave a glaring observation as to where McIlroy struggled in his opening round, saying: “He didn’t putt very well but it all goes back to off the tee.“All of his dropped shots, except for one, were dropped from being wild off the tee and being unable to recover.“We saw him win The Masters so brilliantly but he was second-last for driving accuracy and so he got away with it.McIlroy used just one X-rated word to describe his opening roundGettyMcGinley pointed out where McIlroy falteredGetty“Today Aronimink bit anyone who hit it in the rough.“You miss fairways at your peril around here as the greens are treacherous. You need to hit the fairway to have control.”McIlroy faces conduct violation after club slamHis quest to secure a seventh major title, his third PGA Championship, got off to a tough start before he made it onto the course.Preparations were thrown into chaos due to a blister underneath the nail of his pinky toe.Some DIY treatment was required, and McIlroy said “no” when asked if it was bothering him throughout the round, but something was clearly off.Frustrations got the better of him, and it began when he had words with spectators who had built a makeshift stand at the 14th tee.McIlroy slammed his club and faced a conduct violation during the opening roundGettyTensions reached boiling point after a wayward drive later in his round hooked deep into the rough.In a rare display, McIlroy slammed his club into the turf, drawing a plethora of gasps from the crowd.Under the PGA Tour’s code of conduct, slamming a club usually falls under the category of unprofessional conduct.It’s not known if McIlroy was officially warned, but it’s expected that they will be stricter after Sergio Garcia’s meltdown at Augusta.The Masters champion will be hoping to bounce back on Saturday, otherwise his weekend could be over quicker than he expected.