In 1252, Yorikage served as a messenger who conveyed the news of Prince Munetaka's entry to Kamakura to the Imperial Court, and in 1253, at the age of 25, he became a member of Hikitsukeshu (Coadjustor of the High Court) of the shogunate together Yasumori.
建長4年（1252年）、宗尊親王の鎌倉入りを朝廷に伝える使者を務め、翌建長5年（1253年）に25歳で泰盛と共に幕府の引付衆となる。