Rory McIlroy began his second round with a moment of magic, but even that and a late rally saw him end it needing to make history to win the weather-affected 99th US PGA Championship.
McIlroy was in danger of missing the halfway cut for the fourth time in his last seven major appearances after dropping four shots in the space of five holes at Quail Hollow.
And although he birdied the next two and came agonisingly close to making it a hat-trick on the ninth, his final hole of the day, the 28-year-old's second successive 72 left him two over par and 10 shots off the lead shared by Kevin Kisner and Hideki Matsuyama.
No player has ever won the US PGA after trailing by more than nine strokes after 36 holes, which was also bad news for the grand-slam chasing Jordan Spieth, who trails by 11 after a 73.
Kisner looked certain to lead at the halfway stage after carding a second straight 67 before the threat of lightning forced the players off the course and led to a delay of an hour and 43 minutes.
When play resumed, Matsuyama took advantage of the rain-softened course to card his fourth birdie in succession on the 15th and also picked up a shot on the 17th to join Kisner on eight under par.
The world number three's 64 e stablished a course record for the new Quail Hollow layout, just five days after he equalled the course record with a closing 61 to win the WGC-Bridgestone Invitational.
Former world number one Jason Day carded a 66 to finish six under after playing partner Dustin Johnson ran ahead to tee off on the 18th before play was called off due to darkness, allowing the whole group to finish the hole.
Italy's Francesco Molinari and South Africa's Louis Oosthuizen were a shot further back as play finished in almost farcical fashion in the rush to get finished, Molinari matching Matsuyama's 64 and Oosthuizen returning a 67.
McIlroy, whose only major victory when trailing after 36 holes came when he was two behind in the 2012 US PGA, admitted his situation could easily have been a lot worse, especially after he carved his second shot on the 591-yard 10th over the crowd and saw it bound down a cart path which runs along the side of the 11th.
The ball eventually came to rest just off the path and left the world number four with a seemingly impossible third shot through an avenue of trees, but he produced a brilliant low pitch which bounced off the path, through a bunker and ran across the green before stopping on the fringe.
"If you're ever down there, it's 110 yards," joked with reporters after chipping to two feet and tapping in for par.
Speaking after his round, McIlroy added: "I dropped it in a pretty bad lie, so I couldn't carry it over the cart path. So I hit a six iron and just said, 'okay, I'll bounce it up the cart path and see where this goes'.
"Luckily it got out of the bunker and on to the other side. That could have been a six or a seven quite easily so to get away with a five, I actually felt pretty good about myself going to the next tee."
Kisner's best finish in his previous 11 majors is a tie for 12th in the 2015 US Open, but the 33-year-old from South Carolina made the most of his local knowledge to card three birdies, an eagle and a solitary bogey.
" I've been upset with how I've played in the majors so far in my career," Kisner said. "I feel like I have the game to compete and (have had) tons of 30th to 40th, 50th-place finishes.
"This is probably the easiest one I've had to prep for because I know the golf course so well and I've been up here a lot.
"I 've spent every Thanksgiving and Christmas in Charlotte from childhood to marriage, got a lot of ties to Quail Hollow. My brother-in-law's father is a founding member here. "
At the other end of the leaderboard, Phil Mickelson finished 11 over par on his 100th major appearance to miss just his second halfway cut in 25 US PGA starts.
And defending champion Jimmy Walker also bowed out despite a 69 which was a 12-shot improvement on his opening 81.