Sense entertaining game has new pre-match fun (4,5)
I believe the answer is:
stag night
'pre-match fun' is the definition.
(fun before a wedding or match)
'sense entertaining game has new' is the wordplay.
'sense' becomes 'sight' (sight or vision is a sense).
'entertaining' is an insertion indicator (inviting in, as for dinner).
'game' becomes 'tag' (children's playground game).
'has' means one lot of letters go next to another.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'tag'+'n'='tagn'
'sight' going around 'tagn' is 'STAG NIGHT'.
(Other definitions for stag night that I've seen before include "Final fling" , "Celebration before wedding" , "Rowdy party" , "when men behave badly?" , "Premarital do" .)