Improved, he can dribble during final (8)
I believe the answer is:
enhanced
'improved' is the definition.
(similar in meaning)
'he can dribble during final' is the wordplay.
'dribble' is an anagram indicator (I've seen 'dribbles' mean this (dribble can mean to move a ball in sports)).
'during' is an insertion indicator.
'final' becomes 'end' (synonyms).
'he'+'can'='hecan'
'hecan' anagrammed gives 'hance'.
'hance' inserted into 'end' is 'ENHANCED'.
(Other definitions for enhanced that I've seen before include "Increased the attractiveness of, improved" , "Improved (upon)" , "Improved in quality" , "Improved or increased the value" , "Heightened" .)