Stand against Pope: so beaten! (6)
I believe the answer is:
oppose
'stand against' is the definition.
(I've seen this before)
'pope so beaten' is the wordplay.
'beaten' indicates an anagram (letters beaten up or destroyed).
'pope'+'so'='popeso'
'popeso' with letters rearranged gives 'OPPOSE'.
(Other definitions for oppose that I've seen before include "Resist, be hostile to" , "'Refute, stand against (6)'" , "Refute - confront" , "Take stand against, resist" , "face" .)