Rewrite pieces penned by journalist (5)
I believe the answer is:
emend
'rewrite' is the definition.
(thesaurus)
'pieces penned by journalist' is the wordplay.
'pieces' becomes 'men' ('man' can be a synonym of 'piece').
'penned by' indicates putting letters inside.
'journalist' becomes 'ed' (short for editor).
'men' going into 'ed' is 'EMEND'.
(Other definitions for emend that I've seen before include "would appear better" , "Edit; make alterations to a draft" , "change" , "Make improvements or corrections" , "Rectify" .)