Ace boxer has tea with politician (5)
I believe the answer is:
champ
'ace boxer' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'tea with politician' is the wordplay.
'tea' becomes 'cha' (cha is a type of tea).
'with' means one lot of letters go next to another.
'politician' becomes 'MP' (Member of Parliament).
'cha'+'mp'='CHAMP'
'has' is the link.
Can you help me to learn more?
(Other definitions for champ that I've seen before include "Fret impatiently; winner" , "Supreme competitor" , "boxer who is top dog?" , "Gnaw; winner (abbr.)" , "first place" .)