A horse trained by Austy Coffey at Swan Hill has returned a positive swab to caffeine.
Racing Victoria stewards announced on Wednesday a urine sample taken from the Coffey-trained Burrum's Buzz after his win in a 1200m maiden at Swan Hill in September contained caffeine and its metabolite theophylline which are prohibited.
Coffey has been told of the confirmatory findings while stewards are continuing their investigation.