Old magistrate coming in here eventually (5)
I believe the answer is:
reeve
'old magistrate' is the definition.
(historical type of magistrate or judge)
'in here eventually' is the wordplay.
'in' says the answer is hidden in the clue.
'REEVE' is hidden within 'here eventually'.
'coming' acts as a link.
(Other definitions for reeve that I've seen before include "Old-style magistrate" , "Pass the end of a rope through the bailiff" , "fasten rope" , "local official" , "Female ruff - Canterbury tale-teller" .)