One hoping to be successful on points (9)
I believe the answer is:
ballerina
'one hoping to' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'successful on points' is the wordplay.
I cannot really understand how this works, but
'successful' could be 'in' ('in' can be similar in meaning to 'successful') and 'in' is found within the answer.
This explanation may well be incorrect...
'be' acts as a link.
Can you help me to learn more?
(Other definitions for ballerina that I've seen before include "Female classical dancer" , "Female dancer, could be prima" , "girl from the Kirov?" , "lass good at splits?" , "agile performer" .)