Smart player finally participating in European trophies after reflection (6)
I believe the answer is:
spruce
'smart' is the definition.
(synonyms)
'player finally participating in european trophies after reflection' is the wordplay.
'finally' indicates one should take the final letters.
'participating in' indicates putting letters inside.
'european' becomes 'E' (abbreviation e.g. EU).
'trophies' becomes 'cups' (cup is a kind of trophy).
'after reflection' is a reversal indicator.
The last letter of 'player' is 'r'.
'e'+'cups'='ecups'
'r' inserted inside 'ecups' is 'ecurps'.
'ecurps' in reverse letter order is 'SPRUCE'.
(Other definitions for spruce that I've seen before include "Elegant" , "Tidy - fir" , "Neat and smart like pine tree" , "tree with needle-like leaves" , "Evergreen pyramid-shaped trees" .)