Repeat the usual piffle (6)
I believe the answer is:
'repeat' is the definition.
(I know that parrot is a more specific form of the action repeat)
'usual piffle' is the wordplay.
'usual' becomes 'par' (par is an average golf score).
'piffle' becomes 'rot' (I've seen this in another clue).
'the' is the link.
(Other definitions for parrot that I've seen before include "Eg, macaw" , "Mechanically repeat; bird" , "Lory" , "Tropical bird for Pat Orr" , "Repeat by rote" .)