Beat learned, bad for Glenn Miller perhaps? (10)
I believe the answer is:
bandleader
'glenn miller perhaps?' is the definition.
(I know this)
'beat learned bad' is the wordplay.
'beat' indicates an anagram.
'learned'+'bad'='learnedbad'
'learnedbad' anagrammed gives 'BANDLEADER'.
'for' is the link.
(Other definitions for bandleader that I've seen before include "Music director" , "Conductor, perhaps" , "Music supremo" , "Ted Heath was one" , "Top musician" .)