A hunger to join team next door (9)
I believe the answer is:
alongside
'next door' is the definition.
(I've seen this before)
'a hunger to join team' is the wordplay.
'hunger' becomes 'long' (both can mean to crave).
'to join' means one lot of letters go next to another.
'team' becomes 'side' (both can mean a sports team).
'a'+'long'+'side'='ALONGSIDE'
(Other definitions for alongside that I've seen before include "Lying close to" , "Parallel to" , "Adjacent to" , "Next to - alien dogs (anag)" , "Aligned so as to be next to, as ship moored to pier" .)