Thespian is typecast in part as one kind of player (7)
I believe the answer is:
pianist
'one kind of player' is the definition.
'thespian is typecast in part' is the wordplay.
'in part' says the answer is hidden in the clue.
'PIANIST' is hidden in the letters of 'thespian is typecast'.
'as' is the link.
(Other definitions for pianist that I've seen before include "Key expert" , "Instrumentalist" , "Key worker," , "One tickling the ivories" , "Ivories tinkler" .)