Endless battle to secure first couple of points in game (5,4)
I believe the answer is:
water polo
'points in game' is the definition.
'water polo' can be an answer for 'game' (water polo is a kind of game). I am not sure about the 'points in' bit.
'endless battle to secure first couple' is the wordplay.
'endless' means to remove the last letter.
'battle' becomes 'waterloo' (p8p5 battle).
'to secure' is an insertion indicator (inserted letters are secured inside).
'first couple' becomes 'po' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'waterloo' with its final letter removed is 'waterlo'.
'waterlo' placed around 'po' is 'WATER-POLO'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for water polo that I've seen before include "Team sport played in a swimming pool" , "Game played by teams of swimmers with large ball" , "Swimming pool game" , "event" , "Sport for swimmers" .)