A soccer official briefly in Wellington? Quite the opposite! (8)
I believe the answer is:
barefoot
'quite the opposite' is the definition.
I can't judge whether this definition defines the answer.
'a soccer official briefly in wellington?' is the wordplay.
'soccer official briefly' becomes 'ref' (short for referee; 'briefly' indicates an abbreviation).
'in' means one lot of letters goes inside another.
'wellington?' becomes 'boot' (wellington is a kind of boot).
'a'+'ref'='aref'
'aref' placed within 'boot' is 'BAREFOOT'.
(Other definitions for barefoot that I've seen before include "Unshod" , "Shoeless" , "without protection for lowest members" , "Without shoes and socks" , "'-------- in the Park', Neil Simon play filmed in 1967 with Jane Fonda and Robert Redford" .)