User blog comment:Xilinoc/Ch. 683 - The Dark Side of Two World Ends/@comment-2211792-20160721122008/@comment-5398287-20160721142829

Yep, it's been established that in order to take down the average Sternritter, you need either a Bankai or an ungodly amount of power while in Shikai (e.g. Yamamoto, Kenpachi, and Ichigo).