Dog in the evening sun (6)
I believe the answer is:
setter
I believe this clue is a double definition.
'dog' is the first definition.
(setter is a type of dog)
'evening sun' is the second definition.
(the sun sets in the evening)
'in the' acts as a link.
(Other definitions for setter that I've seen before include "Dog trained to point at game" , "who is giving you problems right now?" , "Puzzle creator" , "Silky-coated gun dog" , "Breed of dog - crossword compiler" .)