I had a bit of shaky start with a bogey on 10th, a par-5 and that was a disappointment, as you don't want to let go of the par-5s and certainly not drop a shot there.
McIlroy said he required "two 67s" to have a "really good chance" after finishing his first 36 holes on two over, but instead hit a two-over-par 73 which included five bogeys. The ball bounced high off a rock and settled into what he called "the worst lie I've seen all week" in the deep Bermuda grass. Overall the putting has been the key factor. I made a birdie and then a couple of pars. "That may have helped".
What he hasn't done yet is win a major. "Keep knocking on the door and someday it will open".
Sailing along with a two-shot lead, Kisner pulled a shot into the water at the 16th and had his bogey-putt spin out of the hole for a double.
Seventh-ranked Jason Day, the 2015 PGA Championship victor and last year's runner-up, fired a 66 to stand third on 136 and he praised Matsuyama's commitment to success.
Of the 15 players who remained under par, Louis Oosthuizen was the only one who had won a major, and that was seven years ago (the 2010 British Open).
While Kisner was the story early in the day, the weather took the stage as the afternoon wave of players took to the course.
American Chris Stroud, in the last group off the 10th tee on Friday, is the top contender among those yet to finish their second round. It might seem like a lot the way Matsuyama and Kisner are playing, but it doesn't to Thomas.
"When we got delayed, the whole course changed with regards to how receptive it was", Day said. The previously slumping Australian had five birdies and an eagle - his second straight on the par-five seventh hole - to get to six under for the tournament.
Starting the proceedings at six-under, Day even went to seven-under with a birdie, but by the time the front nine ended, he was five-under. "When I start hitting it the way I am now, I play well". "But take him out of the equation, I feel like I'm still right there in the tournament". "But whether it's the best that I've ever played in my career, I'm not sure", he said.
Hideki Matsuyama barely missed a birdie putt on the 18th hole that would have given him sole possession of the lead at the PGA Championship.
Fourth-ranked Rory McIlroy fired his second consecutive 72 to stand 10 shots adrift.