Confront someone winning by four, perhaps? (6,2)
I believe the answer is:
square up
'confront someone' is the definition.
I can't judge whether this definition defines the answer.
'winning by four perhaps?' is the wordplay.
'winning' becomes 'up' (I've seen this in other clues).
'by' is a charade indicator (letters next to each other).
'four perhaps?' becomes 'square' (I am not sure about this - if you are sure you should believe this answer much more).
'up' after 'square' is 'SQUARE UP'.
Can you help me to learn more?
(Other definitions for square up that I've seen before include "Pay a debt" , "prepare to fight" , "Settle" .)