An account by the man will produce discomfort (4)
I believe the answer is:
ache
'discomfort' is the definition.
(I've seen this in another clue)
'an account by the man' is the wordplay.
'an account' becomes 'ac' (abbreviation).
'by' says to put letters next to each other.
'the man' becomes 'he' (he refers to a man).
'ac'+'he'='ACHE'
'will produce' acts as a link.
(Other definitions for ache that I've seen before include "Take an aspirin for it" , "Hanker" , "Longing" , "Suffer dull pain" , "Twinge" .)