Alan resolved to maintain a bit of defiance - a court winner (5)
I believe the answer is:
nadal
'alan resolved to maintain a bit of defiance a court winner' is the definition.
I can't judge whether this defines the answer.
'alan resolved to maintain a bit of defiance' is the wordplay.
'resolved' is an anagram indicator.
'to maintain' means one lot of letters goes inside another (inserted letters are controlled or maintained).
'a bit of' suggests taking the first letters.
The initial letter of 'defiance' is 'd'.
'alan' anagrammed gives 'naal'.
'naal' enclosing 'd' is 'NADAL'.
Can you help me to learn more?
(Other definitions for nadal that I've seen before include "Top tennis player" , "Star with a 30 [RACKET]" , "Rafael __, Spanish tennis player" , "court figure" , "tennis champion" .)