End phone call, beginning to feel fine after groin strained (4,3)
I believe the answer is:
ring off
'end phone call' is the definition.
(I've seen this before)
'beginning to feel fine after groin strained' is the wordplay.
'beginning to' suggests taking the first letters.
'after' says to put letters next to each other.
'strained' indicates anagramming the letters.
The initial letters of 'feel fine' is 'ff'.
'groin' with letters rearranged gives 'ringo'.
'ff' put after 'ringo' is 'RING OFF'.
(Other definitions for ring off that I've seen before include "Hang up" , "Slam down phone" , "Terminate a call" , "Finish speaking" , "Christian --, fashion designer" .)