Sutuhu was too young to succeed his father in 13 AD, so his uncle Wulei became chanyu, and he was demoted down the line of succession.
Huduershidaogao's successor Wudadihou only lived for a few months before he died and was succeeded by his brother Punu in 46 AD.
Sutuhu received warning of their advice to Punu and in retaliation gathered some 50,000 men to attack the officers.
Punu's response to this challenge was lackluster and sent only some 10,000 men, who fled at the sight of Sutuhu's larger army.
Bi tried to absorb the remnants of Aojian's men but they were confronted by the Northern Xiongnu, who put them to rout.