Player's foul in a miscue, almost (8)
I believe the answer is:
musician
'player's' is the definition.
('musician' can be a synonym of 'player')
'foul in a miscue almost' is the wordplay.
'foul' indicates anagramming the letters.
'almost' means to remove the last letter (most of the word but not all of it).
'in'+'a'+'miscue'='inamiscue'
'inamiscue' with its final letter taken off is 'inamiscu'.
'inamiscu' is an anagram of 'MUSICIAN'.
(Other definitions for musician that I've seen before include "Composer or performer of vocal or instrumental sounds" , "Minus CIA, one can compose or play" , "Kennedy, O'Conor or Galway, say" , "Cellist or violinist" , "Although minus CIA, one plays" .)