Ahead of the best, apt to win (2,3)
I believe the answer is:
on top
'ahead' is the definition.
(I've seen this in another clue)
'best apt to win' is the wordplay.
I cannot quite understand how this works, but
'best' could be 'top' (top can mean the very best) and 'top' is located in the answer.
The remaining letters 'on' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'of the' is the link.
Can you help me to learn more?
(Other definitions for on top that I've seen before include "Leading" , "Winning" , "At the summit or in superior position" , "In a dominant position" .)