Drums thundered and priests chanted as sumo's newest grand champion strode onto the public stage Friday in a ceremony to mark his promotion to the ancient Japanese sport's highest rank.

Sumo is facing a potential chasm at the top of the ancient sport for the first time in over 30 years after the only yokozuna, Terunofuji, announced his retirement on Friday.

Yokozuna Hakuho has retired after a glorious sumo career of more than two decades that has not only seen him shatter many records but also raised serious questions about the future of the ancient ...