Welsh centre joined Sydney team mid-year (7)
I believe the answer is:
swansea
'welsh centre' is the definition.
The answer and definition can be both locations as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'joined sydney team mid-year' is the wordplay.
'joined sydney team' becomes 'swans' (I can't explain this - if you can you should believe this answer much more).
'mid' says to take the centre (mid- can mean the middle of something).
The centre of 'year' is 'ea'.
'swans'+'ea'='SWANSEA'
Can you help me to learn more?
(Other definitions for swansea that I've seen before include "Welsh port" , "Birthplace of Dylan Thomas" , "South Wales port" , "South Wales city" , "Ecstasy, a win! (anag)" .)