User blog comment:Xilinoc/Ch. 556 - The Wolfsbane/@comment-29183117-20131106152315/@comment-11051098-20131106174617

All the captains and the lieutenants who possess Bankai were given the Shin'eiyaku pill, hollowfying their Bankai for a slight moment. I think the new look of Sajin's Bankai is caused by the hollowfication. At least partly.