Vessel is entering race (8)
I believe the answer is:
canister
'vessel' is the definition.
(I've seen this before)
'is entering race' is the wordplay.
'entering' indicates putting letters inside.
'race' becomes 'canter' (I can't explain this - if you can you should believe this answer much more).
'is' inserted inside 'canter' is 'CANISTER'.
Can you help me to learn more?
(Other definitions for canister that I've seen before include "Metal food container" , "Container for e.g. tea" , "Storage container, for tea say" , "Metal container for storing dry foods" , "Tea-caddy" .)