Mafia boss, one in time for martial art (8)

I believe the answer is:

capoeira

'martial art' is the definition.
(Brazilian martial art)

'mafia boss one in time' is the wordplay.
'mafia boss' becomes 'capo' (head of a crime syndicate).
'one' becomes 'i' (Roman numeral).
'in' indicates putting letters inside.
'time' becomes 'era' (era is a kind of time).
'i' going inside 'era' is 'eira'.
'capo'+'eira'='CAPOEIRA'

'for' acts as a link.

I've seen this clue in The Times.

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