Akio Ōtsuka
Appearing in only five episodes of the series, this version of Casey does not play a role as central as his comic book counterpart: He doesn't have a friendship with Raphael, nor a relationship with April – he doesn't even encounter her until season 5's "Leonardo Cuts Loose", though later they do team up in episodes "Night of the Rogues" and "Cyber-Turtles". Casey was voiced by Pat Fraley. In the Japanese version, he was voiced by Issei Futamata and Akio Ōtsuka (NHK-BS2 Version).