User blog comment:Godisme/Everything But The Rain Op. 2 "The Rudiments"/@comment-1534479-20130307041834/@comment-4924995-20130307103005

I think by the time Rukia became a Shinigami, Toushirou was already the captain of the 10th Squad. The bigger question is, how didnt Matsumoto realise that Ichigo's father was Captain Shiba when she went to his house during the early stages of the Arrancar Arc.