I will follow Manchester United football team initially in civilian gear (5)
I believe the answer is:
mufti
'civilian gear' is the definition.
(I've seen this before)
'i will follow manchester united football team initially' is the wordplay.
'will follow' means one lot of letters go next to another.
'initially' indicates taking the first letters.
The first letters of 'manchester united football team' is 'muft'.
'i' put after 'muft' is 'MUFTI'.
'in' is the link.
(Other definitions for mufti that I've seen before include "Civvies; Muslim legal expert" , "Civilian dress, worn by an off-duty soldier, say" , "Non-military clothing" , "Civilian attire" , "Plain clothes - Muslim law expert" .)