Such a man can become a prisoner (3)
I believe the answer is:
con
'prisoner' is the definition.
(abbreviation for 'convict')
'such a man can become a' is the wordplay.
I cannot quite understand how this works, but
'man' could be 'n' (knight, a man in chess) and 'n' is located in the answer.
The remaining letters 'co' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for con that I've seen before include "Swindle or trick someone" , "Prisoner (sl.)" , "Study; steer" , "Not supporting" , "Have a reason not to" .)