Post office worker admits second-rate, shoddy work (9)
I believe the answer is:
potboiler
'shoddy work' is the definition.
'potboiler' can be an answer for 'work' (I have seen 'hasty work' mean 'potboiler' so perhaps 'work' could also mean 'potboiler'). I am not certain of the 'shoddy' bit.
'post office worker admits second-rate' is the wordplay.
'post office' becomes 'po' (abbreviation).
'worker' becomes 'toiler' (toiler is a kind of worker).
'admits' indicates putting letters inside (to admit is to allow in).
'second rate' becomes 'b'.
'toiler' enclosing 'b' is 'tboiler'.
'po'+'tboiler'='POTBOILER'
Can you help me to learn more?
(Other definitions for potboiler that I've seen before include "Money-making book" , "likely to be steamy?" , "Book, film, etc, produced just for the money" , "Book of little merit written to make a quick profit" , "Book written just for the money" .)