Charlotte - Threatening weather prompted officials to suspend second-round play on Friday at the PGA Championship, with a thunderstorm coming near the Quail Hollow course.
Players were pulled off the course due to dangerous conditions while spectators were advised to seek shelter, even though there was hope play might resume before dark.
American Kevin Kisner was leading in the clubhouse on eight-under par 134, but Japan's Hideki Matsuyama was making a charge at six-under with four holes remaining in his second round.
Third-ranked Matsuyama had made five birdies in a bogey-free round, including three in a row before the horn sounded to halt play after he struck his tee shot at the par-5 15th hole.
Australia's Jason Day, the 2015 PGA winner and last year's runner-up, was third at five-under after 10 holes of his second round.
He was four-under for the day after an eagle at the par-5 seventh and three birdies in a row when play was halted.