Scottie Scheffler, Viktor Hovland and Corey Conners delivered clutch birdies and grinded out par saves to share the lead late in Friday's second round of the PGA Championship as rivals stumbled at rainy Oak Hill.

Second-ranked American Scheffler, last year's Masters champion, and Canada's Conners, chasing his first major title, each fired two-under-par 68 to finish 36 holes level at the top on five-under 135.

"Felt like I grinded it out pretty well," Scheffler said. "Didn't make as many birdies as I would have liked but I had a pretty good number."

Conners, who won his second PGA Tour title at last month's Texas Open, worked magic with his putter when needed.

"Very pleased," Conners said. "The conditions were tricky out there, faced some wind, some rain. Game was solid. I made a bunch of key putts to keep momentum going, and that was really the key to the day."

Norway's 11th-ranked Hovland, also seeking a first major crown, sank a five-foot birdie putt at the 18th hole to shoot 67 and make it three at the top.

"The score has been great but the way I've plodded my way around here, very pleased with that," he said. "I was trying to give myself the most stress-free pars and a couple birdie looks as well."

American Bryson DeChambeau was still on the course at four under with Americans Keegan Bradley and Justin Suh and England's Callum Tarren still out at two under.

Scheffler, who would return to world number one with a victory, opened with back-to-back birdies but slid with a bogey at the seventh.

He answered with an 11-foot birdie at 14 and a tap-in birdie at the par-3 15th but missed a 12-foot par putt at 18 to close with a bogey.

Back-nine starter Conners, ranked 29th, sank nine-foot birdie putts at the par-5 13th and par-3 15th, then made a 12-foot par putt at 17 and a 10-footer to par 18. He added a 21-foot birdie putt at the second but fell back with a bogey at seven.

Hovland also made birdie putts from just outside 10 feet at the first and just inside 20 feet at the second, made bogey at the third but began the back nine with a birdie.

DeChambeau, the 2020 US Open champion who has made the break to the Saudi-backed LIV golf circuit, answered a three-putt bogey at the par-3 third and double bogey at six with birdies at the par-3 11th, par-5 13th and par-4 14th.

Four-time major winner Brooks Koepka birdied three of the last four holes to shoot 66 and stand on 138.

"Knew I needed a good round," said Koepka. "Happy to shoot under par and get back in the race."

Justin Rose, the 2013 US Open and 2016 Rio Olympic champion, and Canada's Taylor Pendrith were on 139.

Rose, who won in February at Pebble Beach for his first triumph since 2019, could be the first Englishman to win the PGA Championship since Jim Barnes in 1916 and 1919.

Four-time major winner Rory McIlroy, chasing his first major victory since 2014, fired a 69 to stand on level par 140. He found water and made bogeys at six and seven but had birdie putts of 44 feet at nine, seven feet at 14 and 16 feet at 18.

"It was a bit of a grind again," McIlroy said. "I had to score as best as I could. Rode my luck a little bit. Pretty erratic off the tee, Need to tighten it up over the weekend."

World number one Jon Rahm, the reigning Masters champion, struggled but made the cut by following a 76 with a 68.

After going over the projected cut line of five-under with a 10-foot par putt miss at 12, Rahm made three consecutive birdies and reached the weekend on 144 alongside reigning British Open champion Cameron Smith of Australia.

Reigning US Open champion Matthew Fitzpatrick of England closed with back-to-back bogeys to miss the cut on 146.

Jordan Spieth, a three-time major winner trying to complete a career Grand Slam by winning this week, shot 72 to make the cut on the number. A nine-foot birdie putt at 15 and three closing pars got the US star to the weekend despite a left wrist injury.

Defending champion Justin Thomas shot 72 to make the cut on the number.