I am looking for an equivalent of a Chinese saying "If there are no great generals left in Shu, Liao Hua (a military general of Shu) will be the vanguard."
It can be interpreted as "the state of Shu lacked great talents and new blood so that they had to let the elderly Liao Hua to fight in the vanguard". It is basically a situation where an unfit person is forced into a job because no one suitable can be found.