Hideki Matsuyama may share the lead at the US PGA Championship, but felt he hit "too many" bad shots during his stunning second round.
The Japanese world number three fired a brilliant bogey-free seven-under 64 to join Kevin Kisner in the lead at Quail Hollow on Friday.
But Matsuyama - who was affected by the rain delay that will see the second round carry into Saturday - attempted to play down his outing, saying he got somewhat lucky.
"The best shot was my tee shot at 17. The worst shot, there was too many. I can't count them all," he told a news conference.
He added: "Somehow, my worst shots were finding the fairway."
Matsuyama, 25, is a five-time winner on the PGA Tour, while he finished tied for second at the U.S. Open this year.
He is unsure how he will feel heading into Saturday, but refused to say his rivals should be worried.
"I don't know if the other players should be nervous or not, but this is my first experience leading a major, or tied for the lead after 36 holes [sic]," Matsuyama said.
"And so being a new experience, maybe I'll be a little nervous, but on the other hand, I'm looking forward to the weekend and seeing how I do."