Carrier carried by fans at Chelsea (7)
I believe the answer is:
satchel
'carrier' is the definition.
(I've seen this before)
'carried by fans at chelsea' is the wordplay.
'carried by' says the answer is hidden in the clue.
'SATCHEL' is hidden in the letters of 'fans at chelsea'.
(Other definitions for satchel that I've seen before include "What's carried by pupils" , "Schoolbag found in chalets" , "Bag for school books" , "Bag -- latches (anag)" , "Text mark for an insertion" .)