International striker on trial (4,5)
I believe the answer is:
test match
'international' is the definition.
(cricket international)
'striker on trial' is the wordplay.
'striker' becomes 'match' (a match can be struck).
'on' says to put letters next to each other.
'trial' becomes 'test' (synonyms).
'match' put after 'test' is 'TEST MATCH'.
(Other definitions for test match that I've seen before include "Sort of game" , "International sports event" , "Lord's international?" , "International contest" , "may involve man dealing with maiden" .)