However, when he was building this Sanada-maru, other busho suspected that it might be a preparation for Nobushige to switch to the Tokugawa side and were somewhat cautious.
しかし、この真田丸を造る際、大坂方の他の武将は信繁が徳川方に寝返るための下準備と疑っており、少々ながらも警戒していた。