NEWTOWN SQUARE, Pennsylvania, May 14 : Masters champion Rory McIlroy had just one blunt word to describe his woeful opening round of the PGA Championship on Thursday at Aronimink Golf Club that left him with work to do if he hopes to avoid missing the halfway cut."Shit," world number two McIlroy said in the opening response during his media availability when asked to describe his four-over 74.When asked to elaborate, the Northern Irishman blamed his inaccuracy off the tee for his troubles during a round that he ended with four consecutive bogeys."I'm just not driving the ball well enough. It's been a problem all year for the most part," said McIlroy.Show MoreShow Less"I miss it right, and then I want to try to correct it. And then I'll overdo it, and I'll miss it left. It's a little bit of back and forth that way. So that's pretty frustrating, especially when like I pride myself on driving the ball well."McIlroy, who started on the back nine, followed an opening bogey with a birdie at his second hole. After a string of 10 pars he made another bogey that he quickly erased with a birdie at the par-three fifth hole to get back to even par before limping home with four straight bogeys.McIlroy, making just his second start since retaining his Masters title in April, was a betting favourite coming into the week along with world number one Scottie Scheffler.The six-time major champion ended his practice round early on Tuesday because of a blister on his right pinky toe but said it did not bother him during his opening round.The windy conditions at Aronimink also proved to be a challenge for several players."I wasn't expecting it to be as windy today as it was," said McIlroy. "I think it's the breezy conditions that are sort of making the scoring what it is. It's hard to get the ball close."McIlroy now faces an uphill battle to make the halfway cut, let alone win a seventh career major title."I just need to try to figure it out," said the 37-year-old. "I honestly thought I'd figured it out. Coming in here, I hit it well on Sunday at Quail Hollow, and then hit it good at home on Monday. Obviously I had to curtail the practice round Tuesday, but hit it decent yesterday."Once I get under the gun, it just seems like it starts to go a little bit wayward on me."