Kase was absolutely rocked by Nikita Zadorov while attempting to move the puck out of the Leafs zone. Whether the hit was clean or not is debatable, but either way, there was a lot of head contact involved. Kase lost his helmet and didn't look to be feeling well at all as he left the ice. He was taken out of the game for precautionary reasons.
Seeing him at practice wearing a blue jersey means that he has been cleared for contact by the Leafs' medical team. Fantastic news for Kase, the Leafs and the fans. Kase should be in the lineup tomorrow night when they face off against the Vancouver Canucks.