Pet in the evening sun (3,6)
I believe the answer is:
red setter
'pet' is the definition.
(I've seen this before)
'in the evening sun' is the wordplay.
'in the' becomes 'red' (I am not sure about this - if you are sure you should believe this answer much more).
'evening sun' becomes 'setter' (the sun sets in the evening).
'red'+'setter'='RED SETTER'
Can you help me to learn more?
(Other definitions for red setter that I've seen before include "supplier of crosswords to the Daily Worker?" , "description of evening sun?" , "My best friend" , "Barker" , "Pet" .)