Odds on champion horse showing winning quality? (7)
I believe the answer is:
sparkle
'winning quality?' is the definition.
'sparkle' can be an answer for 'quality?' (sparkle is a kind of quality). I am unsure of the 'winning' bit.
'odds on champion horse' is the wordplay.
'odds' becomes 'sp' (betting abbreviation for starting price).
'on champion horse' becomes 'arkle' (I can't explain this - if you can you should give a lot more credence to this answer).
'sp'+'arkle'='SPARKLE'
'showing' acts as a link.
Can you help me to learn more?
(Other definitions for sparkle that I've seen before include "Shine brightly" , "Scintillate" , "Flash brightly" , "Glittering light" , "Shine (wittily)" .)