Spotted as it ran towards the home turn (7)
I believe the answer is:
stained
'spotted' is the definition.
(synonyms)
'as it ran towards the home turn' is the wordplay.
'ran' indicates an anagram (letters have run around).
'towards' says to put letters next to each other (I've seen this in other clues).
'the home' becomes 'den' (an animal's home).
'turn' says the letters should be written backwards.
'den' back-to-front is 'ned'.
'as'+'it'='asit'
'asit' is an anagram of 'stai'.
'stai'+'ned'='STAINED'
(Other definitions for stained that I've seen before include "___ glass" , "Like many church windows" , "Soiled" , "Marked, discoloured" , "Church feature - side sold was wanting (anag)" .)