England's Paul Casey birdied his 14th and 15th holes in a round of 68 to be sharing fourth place at five-under par.
Tiger Woods got his putter to cooperate a little better on Saturday.
Woods' sixth straight third round of par of better was promising, but it wasn't good enough to make up a lot of ground - and certainly not as bold as the moves from Phil Mickelson (64) or Rory McIlroy (66).
The 30-year-old major victor also drained a 8m birdie putt on the par three 17th, one of three holes known as the "Green Mile" due to their reputation as the toughest finishing stretch on the PGA Tour. He made birdie on the two scoring holes on the front nine.
Tiger Woods reacts to his putt on the 12th hole.More news: Fox Moves to Revive Tim Allen Comedy Series 'Last Man Standing'
"I'm close", said Woods.
Uihlein's start at Quail Hollow was nothing to write home about. I leave it right where I need to leave it, right below the hole, and I miss it. He'll play in the final group on Sunday alongside Day, and a win would be his first since the 2012 Barclays at Bethpage Black. "There's going to be probably, I'm guessing, 15 guys or so with a chance on Sunday". But I'm just taking tomorrow that I've got to try and extend that lead every single time I'm up against someone.
Englishman Tyrrell Hatton went one better than McIlroy with his opening effort in Charlotte after finishing birdie-birdie, to share the clubhouse lead with American Peter Malnati.
Alone in second is Nick Watney, who shot a five-under 66 to get to eight-under 205 for the tournament.
Mickelson wasn't that wild - three bogeys, two birdies, another 72, and he made the cut with one shot to spare.More news: Matt Ryan, Falcons Agree To Record-Setting New Contract
"I'm kind of free-wheeling it at this point", he said.
Woods was one of several golfers who began the third round at 2 over par, but he took advantage of playing in the morning under overcast skies and an easier course setup than the previous two rounds. 8 and 9. He double-bogeyed No. 8, followed by a triple bogey on nine.
"For me it's the most special tournament that we play and it's the one everyone desperately wants to win, but even if I was going for my first major, it's still tough to win". What really pleased him was a 7-iron from 195 yards to pin-high on the par-3 17th, and the birdie putt he made from just inside 30 feet.
"I was so close to shooting about 7 under on that back nine, " Woods said after shooting 34 on the closing nine holes. "I still didn't have enough pace on a couple that I left on the lip". But I wasn't at all, it was actually the other way, it was more clubface.More news: World Press Freedom day 2018, for the importance of press and media