Opponent in Roman times (4)

I believe the answer is:

anti

'opponent' is the definition.
(someone opposed to something)

'in roman times' is the wordplay.
'in' indicates a hidden word.
'ANTI' is hidden within 'roman times'.

(Other definitions for anti that I've seen before include "Prefix meaning against" , "Against, informally" , "Opposition member" , "one opposing?" , "Policy's opponent" .)

I've seen this clue in The Times.

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