Dog racing venue cancels opening fixture (7)
I believe the answer is:
scottie
'dog racing venue' is the definition.
'scottie' can be an answer for 'dog' (I've seen this before). I am not certain of the 'racing venue' bit.
'cancels opening fixture' is the wordplay.
'cancels opening' becomes 'scot' (I am not sure about this - if you are sure you should believe this answer much more).
'fixture' becomes 'tie' (I've seen this before).
'scot'+'tie'='SCOTTIE'
Can you help me to learn more?
(Other definitions for scottie that I've seen before include "Breed of terrier" , "Type of terrier" , "animal" , "Dog" .)