What hopeful snooker player did — lost form, dramatically? (4,2,3)

'what hopeful snooker' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'player did lost form dramatically?' is the wordplay.
I cannot really understand how this works, but
'player' could be 'e' (I've seen this in other clues) and 'e' is located in the answer.
'form' could be 'top' (top is a kind of form) and 'top' is found in the answer.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?