Batting streak, reportedly to no avail (2,4)
I believe the answer is:
in vain
'to no avail' is the definition.
(synonyms)
'batting streak reportedly' is the wordplay.
'batting' becomes 'in' (as in batting or being 'in' in cricket).
'streak' becomes 'vein' (vein can mean a streak or strip).
'reportedly' shows a homophone (sound like).
'vein' is a homophone of 'vain'.
'in'+'vain'='IN VAIN'
(Other definitions for in vain that I've seen before include "To no purpose" , "Fruitlessly" , "Uselessly, a waste of time" , "Without success or result" , "Without effect" .)