Leave a league after lower score at rugby (4,4)
I believe the answer is:
drop goal
'score at rugby' is the definition.
'drop goal' can be an answer for 'score' (I've seen this before). I am not sure about the 'at rugby' bit.
'leave a league after lower' is the wordplay.
I cannot quite see how this works, but
'leave' could be 'go' (to go is to depart or leave) and 'go' is present in the answer.
'a' is within the answer.
'league' could be 'l' (abbreviation) and 'l' is present in the answer.
'lower' could be 'drop' (I've seen this before) and 'drop' is found in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for drop goal that I've seen before include "one scores with over the bar" , "score points?" , "One way of scoring at rugby" .)