NAGOYA, Japan — Bulgarian Kotooshu got off to a shaky start on Sunday in his bid for promotion to sumo's highest rank of grand champion.

Ozeki Kotooshu was shoved off the raised ring by top maegashira Aminishiki to lose his first bout at the Nagoya Grand Sumo Tournament.

Kotooshu, who won the Summer Grand Sumo Tournament in May, comes into the 15-day Nagoya tourney looking for promotion to grand champion but didn't get the start he wanted.

Kotooshu made sumo history in May, becoming the first European to win an Emperor's Cup.

The 25-year-old Bulgarian, whose real name is Kaloyan Mahlyanov, won the summer meet with a 13-1 record

Aminishiki took advantage of a weak faceoff and shoved Kotooshu out in a matter of seconds. Kotooshu would likely be promoted to grand champion if he wins this meet but a perfect record would have made it easier.

Elsewhere, Grand champion Hakuho of Mongolia, who will be out to challenge Kotooshu for the Emperor's Cup, forced out Komusubi Kisenosato for an opening-day win.

Fellow Mongolian grand champion Asashoryu didn't fare as well, losing to komusubi Toyonoshima in the day's final bout at Aichi Prefectural Gymnasium.

Asashoryu forced Toyonoshima to the edge of the ring but touched the dirt surface with his hand as the two wrestlers fell out.

In other major bouts, Chiyotaikai, who needs a winning record in this tourney to maintain his ozeki status, got off to a winning start with an arm thrust that sent No. 2 maegashira Hokutoriki over the edge.

Ozeki Kaio forced out Mongolian Asasekiryu to pick up an opening-day win.

Mongolian Ama, wrestling as a sekiwake, used an arm throw to send No. 3 maegashira Futeno sprawling to the dirt surface.

Ozeki Kotomitsuki twisted down top maegashira Wakanoho to get off to a winning start.