Yokozuna Hakuho came perilously close to fluffing his lines before seeing off fellow Mongolian Harumafuji to win the Spring Grand Sumo Tournament with a perfect 15-0 record on Sunday.

Needing victory to avoid a championship playoff with Estonian sekiwake Baruto (14-1), Hakuho was given his toughest test of the tournament but the yokozuna held his nerve to send ozeki Harumafuji (10-5) down with a textbook overarm throw to clinch his 13th Emperor's Cup.

"He (Baruto) has been in good form in his tournament so I had extra determination to win," said Hakuho.