McIlroy grabbed six birdies in a three under par 69 while Clarke could not wait to remove his left shoe and revealing a nasty blister on the back of his heel after signing for a four over par 76.
While it is just the sixth occasion in 15 rounds that McIlroy has broken 70 at the Quail Hollow course, the world No. 11 capitalised on his length off the tee to birdie three of the four par fives, and also had the putter back on song with his chosen highlights in the round being birdies at the par three sixth and 17th holes.
“I could have squeezed a bit more out of the round but then anything sub-70 was a decent score as the wind was getting up a little there at the end and making the course play tricky,” said McIlroy.
“I played the par fives well, because coming off Augusta where I played the par fives in even par for the week and playing the fives today in three-under par was much better.”
McIlroy had just 28 putts, including posting five one-putts in succession from the fifth hole, this on 18 completely new Bermuda grass greens since being tied 10th a year ago.
In the two weeks since sharing eighth place in the Masters, McIlroy has worked hard on his putting, including using a putting mirror, a chalk line and the tried and true length of string.
“I was standing too close to the ball when I was putting so my eyeline was the far side of the ball, so I basically couldn’t see a straight line,” he said.
“It was like I was aiming about three inches left of the hole, and it seems so simple, and you wonder how a Tour pro makes that mistake.
“So to see six birdie putts drop on these new greens was very pleasing and reassurance of the work I’ve been undertaking on my putting since the Masters.”
McIlroy played alongside Sweden’s Jonas Blixt for the first time and while the Swede is struggling with an arm injury since his share of second at Augusta, McIlroy agreed with Ryder Cup captain, Paul McGinley’s assertion that Blixt shows just the ‘spunk’ needed in a Ryder Cup team.
“Yeah, I agree with Paul exactly, for sure,” said McIlroy.
“Jonas played well in the PGA last year at Oak Hill, and he got himself into contention in the Masters, so he seems to be able to perform well on the big occasions.”
Clarke wasted little time changing into a pair of trainers after his round but refused to seek medical treatment on his blister.
The former British Open winner was hurting more for taking a last hole triple-bogey, where his second shot from 256-yards out cannoned off a tree, and he took three shots to get down from some 40-feet behind the green.
“The blister’s okay but what hurts more is taking a triple on the last, and after hitting a tree so why would you expect anything else,” he said.
“I’d just managed to birdie the hole before to get myself back to one over, but those are the breaks.”
Double Major winning Angel Cabrera of Argentina produced his lowest score all season, a six under par 66, to be the clubhouse leader.
And American Stewart Cink, who played alongside Clarke for a second event running, shares second place on four under par, and like Cabrera, he seeks to win for a first time since capturing a 2009 Major.