Beat United with balls going round the outside (5)
I believe the answer is:
outdo
'beat' is the definition.
(outdoing is a kind of beating)
'united with balls going round the outside' is the wordplay.
I cannot really see how this works, but
'united' could be 'utd' (common abbreviation as in names of sports teams) and 'utd' is found within the answer.
'round' could be 'o' (round can mean a round object) and 'o' is present in the answer.
A single letter 'o' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for outdo that I've seen before include "Be better in performance (than another person)" , "Perform better than another" , "Surpass - overshadow - excel" , "Br superior to (someone)" , "Perform better than surpass" .)