Wimbledon champion we notice inside (4)
I believe the answer is:
wade
'wimbledon champion' is the definition.
(Virginia Wade)
'we notice inside' is the wordplay.
'notice' becomes 'ad' (both can mean an advertisement).
'inside' means one lot of letters goes inside another.
'we' going around 'ad' is 'WADE'.
(Other definitions for wade that I've seen before include "Walk with legs partly immersed" , "Proceed with difficulty" , "Walk through liquid" , "Paddle" , "Virginia who won Wimbledon" .)