The world's second-ranked golfer entered the week with a chance to become the youngest in history to earn a career grand slam, but he shot his second over-par round Friday at the PGA Championship to fall 11 strokes off the lead.
He finished with six birdies in all.
Thorbjorn Olesen, the 27-year-old from Denmark, and American Kevin Kisner are tied for the lead.
Day finds himself two shots out of first place at -6 overall.
Given the size of Quail Hollow, Kisner drew up a simple plan: He identified four or five holes where he could make birdie and he played for par everywhere else. "So that's kind of been my game plan". But I love putting on the surfaces. On the back nine, he had three bogeys in a row from third to fifth, before stemming the rot with a par and then closed the day with three straight birdies for a card of one-under 70 and was Tied-15th.
Kisner birdied three of his final five holes, including a 20-footer on 18.
So far, around Quail Hollow, Kisner has been able to do what no other player has managed - figure out the greens and roll in some decent-length putts. It has also been fortified with thick rough on the outskirts of fairways. "I've got to play better to be on it", Mickelson said. "I can't count them all", said the guy who shot 64.
"You have to drive it in the fairway " that's definitely key", Fowler said.
"The first 15 holes, especially, I was driving the ball very, very well and that made it a bit easier", said the world No. 78, a four-time European Tour victor. "That's already set. It's more so in between the ears, making sure I make the right decisions and not get ahead of myself".
But what really hurt me was the 17th, the middle segment of the "Green Mile", which for me came in the first nine itself.
"I just feel so comfortable, I don't feel like I have to read it and over-read it". "I haven't hit it this well this whole summer". Olesen did the same with six birdies and two bogeys.
In his last five majors, Koepka's worst finish is 13th. "I had a good week in France, but besides that, I haven't really had the results". A nice 14-15 foot for par steadied me and on seventh two good shots to get to around 25 feet and two-putted for par.
The idea is I have to get rid of negativity and also not be over enthusiastic in cases like back-to-back birdies or similar. "If you miss it just by a couple feet from the flag, you can hit a great shot in there and wind up 30 yards away".