Troubled sumo grand champion Asashoryu has announced his retirement. The Mongolian national icon, known for his temperamental nature, leaves the sport amid a recent scandal in which he was accused of seriously injuring a man during a drunken rampage. The Japan Sumo Association (JSA) had ordered an investigation into the incident on Tuesday, leaving him with little option.

“I am grateful for everything. I will retire,” said Asashoryu, 29, who won his 25th Emperor”s Cup at the New Year Grand Sumo Tournament to move into sole possession of third place on the all-time list for most title victories in sumo. “I have caused a lot of trouble in the world. Right now, my head is clear.”

Sumo”s self-styled enfant terrible, Asashoryu is no stranger to controversy and his frequent breaches of protocol have led to an increasingly strained relationship with the sumo establishment. In 2007 he received a two-tournament ban, which sparked a bout of depression, after it was revealed that he had played hooky from a summer regional tour by feigning the degree of his injuries and later taking part in a soccer match in his native Mongolia. Asashoryu has also been censured by the JSA for playing golf with other Mongolian wrestlers, including rival yokozuna Hakuho, immediately before last year”s summer meet.

In a 2003 bout he was disqualified for yanking the hair of compatriot Kyokushuzan, a no-no in sumo. He picked a fight with Kyokushuzan in the locker room afterward and was later accused of smashing the side mirror of the same wrestler”s car.