TOKYO — Bulgarian Kotooshu suffered his first defeat in the 15-day sumo tournament Friday, but still remained on the brink of history as the first European to win an Emperor's Cup.

The 25-year-old Bulgarian rising star looked nervous during a face-off against Japanese wrestler Aminishiki at Tokyo's Ryogoku Kokugikan (sumo stadium), and appeared almost powerless as the 29-year-old Japanese shoved him out of the ring in a matter of seconds.

But the Bulgarian, whose real name is Kaloyan Mahlyanov, was still poised to go down in Japan's sumo history. Kotooshu only needs to win one of his two weekend bouts to become the first European to claim an Emperor's Cup.

His only rival for the title is grand champion Hakuho, but the 23-year-old Mongolian was beaten Friday by 32-year-old Japanese Kotomitsuki, who grabbed Hakuho's belt and quickly threw him out of the ring. He dropped to 10-3.

His archrival and fellow Mongolian grand champion Asashoryu took his fourth defeat from Japanese Kaio.

Asashoryu, 27, was seeking his 23rd Emperor's Cup, but Friday's loss eliminated him from the title race.