Man dropped from show, necessarily (8)
I believe the answer is:
perforce
'necessarily' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
(Other definitions for perforce that I've seen before include "willy-nilly" , "Old word for necessarily, due to circumstances" , "Of necessity" , "without choice" , "Necessarily; inevitably" .)