He just needs one set to finish the match (4)
I believe the answer is:
seth
'he just needs one' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'set to finish the match' is the wordplay.
'set to' becomes 'set' (synonyms).
'finish' suggests the final letters.
The last letter of 'match' is 'h'.
'set'+'h'='SETH'
Can you help me to learn more?
(Other definitions for seth that I've seen before include "In disguise, the brother of Cain and Abel" , "god of Egypt" , "Indian novelist, Vikram" , "Early human" , "said to sound archaic" .)