It’s nothing to him to reach pivotal final! (5)
I believe the answer is:
nadal
'pivotal final' is the definition.
The definition suggests an adjective which matches the answer.
'it's nothing to him' is the wordplay.
'it's nothing' becomes 'nada' (synonyms).
'to him' becomes 'l' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'nada'+'l'='NADAL'
'to reach' is the link.
Can you help me to learn more?
(Other definitions for nadal that I've seen before include "Top tennis player" , "tennis champion" , "Rafael __, Spanish tennis player" , "Star with a 30 [RACKET]" , "court figure" .)