Live event happening involving United and Rovers (7)
I believe the answer is:
bedouin
'rovers' is the definition.
(nomadic Arab people)
'live event happening involving united' is the wordplay.
'live' becomes 'be' (synonyms).
'event' becomes 'do' (do is a kind of event).
'happening' becomes 'in' (happening can mean fashionable or 'in').
'involving' means one lot of letters goes inside another.
'united' becomes 'U' (as in Man U, English football team).
'do'+'in'='doin'
'doin' enclosing 'u' is 'douin'.
'be'+'douin'='BEDOUIN'
'and' is the link.
(Other definitions for bedouin that I've seen before include "Wandering Arab of the Sahara" , "Member of a nomadic tribe of Arabs" , "I dub one (anag)" , "Arab nomadic peoples" , "Desert wanderer" .)