Co-leader Xander Schauffele expects another threat to the lowest round in major golf history in Sunday's final round of the PGA Championship, with an epic shootout possible at rain-softened Valhalla.

Schauffele matched the all-time low major round with a nine-under 62 in Thursday's first round and Irishman Shane Lowry tied him on Saturday, missing a birdie putt at the par-5 18th for what would have been an unprecedented 61.

"There's blood in the water," said Schauffele. "Everyone laughed and then Shane Lowry almost shot 61.

"I imagine someone in that threshold now that it has been done twice is going to shoot something low and post a number early. I imagine that's going to happen. Just staying in my lane is what's going to make me play well."

Third-ranked Schauffele, seeking his first major triumph, shares the 54-hole lead with two-time major winner Collin Morikawa on 15-under 198.

There are 15 players at 10-under or better, the most in any major after 54 holes, crushing the old mark of seven.

Jordan Spieth, needing a win to complete a career Grand Slam, and Rory McIlroy, whose last major win was a decade ago at Valhalla, are seven shots back and world number one Scottie Scheffler is eight back -- just like Lowry was before his Saturday charge.

"A lot of guys took it low to climb their way up," Morikawa said. "I assume tomorrow is going to be the same."

Reigning Olympic champion Schauffele tried to downplay the importance of a first major crown, which would also end a win drought dating to the 2022 Scottish Open.

"It really is just a result," he said. "But yeah, it would mean a ton."

Morikawa says fans want to see a major breakthrough by Schauffele more than want to see him take a third major at age 27.

"It's nice to have people root for you and I feel like people aren't rooting for me out here," Morikawa said. "They like a good story. Xander hasn't won one, other guys, whatever it may be. But, you know, I could care less."

Morikawa won the 2021 British Open and 2020 PGA Championship and will use those major wins to help Sunday.

"I'm going to tap in just that mental state I've been in, not only those two, but in other tournaments I've played well in," Morikawa said.

"The goal before my tee time is just to be mentally sharp by that first hole. Tomorrow is just going to put everything I have out there and see how it plays out."

Schauffele says he wants to play from top the leaderboard rather than chase from behind.

"You want the lead," he said. "Against these guys, you want as many shots as you can possibly take, no matter how nerve-racking it can be."

- 'Hitting the ball nice' -

Schauffele said his 62 "felt super easy" but since then it has been harder.

"Felt like I've had to work for a lot of my birdies the last two days. Haven't been able to make many putts," he said. "I'm hitting the ball pretty nice. If I can just get the putter going a little bit, it should free me up."

Morikawa isn't worried so much about the start as the finish.

"I've made birdies throughout this entire golf course, so it's not like I have to get all my birdies in through the first six holes," he said.

"There are going to be guys that take it very low early on and there are a ton of guys that could do a lot tomorrow.

"If I need to press, it's going to be in the last two to three holes -- if I need to."