Under the doctor, upset priest is easily managed (6)
I believe the answer is:
docile
'easily managed' is the definition.
(I've seen this before)
'under the doctor upset priest' is the wordplay.
'under' says to put letters next to each other.
'the doctor' becomes 'doc' ('doc' can be a synonym of 'doctor'**).
'upset' says the letters should be written in reverse.
'priest' becomes 'eli' (I've seen this before).
'eli' reversed gives 'ile'.
'doc'+'ile' is 'DOCILE'.
'is' is the link.
(Other definitions for docile that I've seen before include "Willing to be taught or led" , "Meek and biddable" , "'Pliant, submissive (6)'" , "Gentle and pliant" , "Coiled in obedient way" .)