Musical gets rubbish review from telephonist (8)
I believe the answer is:
operator
'telephonist' is the definition.
(I've seen this before)
'musical gets rubbish review' is the wordplay.
'musical' becomes 'opera' (I've seen this before).
'gets' is a charade indicator (letters next to each other).
'rubbish' becomes 'rot' (both can mean nonsense).
'review' says the letters should be written backwards.
'rot' in reverse letter order is 'tor'.
'opera'+'tor'='OPERATOR'
'from' is the link.
(Other definitions for operator that I've seen before include "Wheeler-dealer - telephonist" , "Person running a business" , "Controller, of a machine say" , "Poor rate for a businessman" , "Switchboard employee" .)