In goalless game, United better (5)
I believe the answer is:
outdo
'better' is the definition.
(to outdo is to beat or do better than)
'in goalless game united' is the wordplay.
'in' indicates putting letters inside.
'goalless game' becomes 'oo' (resembles 0-0 score).
'united' becomes 'utd' (common abbreviation as in names of sports teams).
'oo' going around 'utd' is 'OUTDO'.
(Other definitions for outdo that I've seen before include "Surpass, go one better than" , "Surpass someone at something" , "Exceed" , "Overtake" , "Surpass - overshadow - excel" .)