The betting favorite going into the 1968 Kentucky Derby, Forward Pass finished second, but winner Dancer's Image was disqualified to last place after traces of phenylbutazone were discovered in the mandatory post-race urinalysis.
"[7] It was revealed that Dancer's Image had been plagued by sore ankles and on the Sunday prior to the Kentucky Derby, his handlers had a veterinarian give the horse a phenylbutazone tablet, a non-steroidal anti-inflammatory drug (nsaid)[8] commonly used to relieve inflammation of the joints, which was legal at many race tracks in the United States but not at Churchill Downs.
When the horse's post-Derby urinalysis revealed the phenylbutazone, his owner and handlers believed someone else may have been motivated to give the colt another dose of the drug, and they filed an appeal of the disqualification.
A victory by Forward Pass in the Belmont Stakes would make him the first Triple Crown winner in twenty years and many fans, experts, and racing commentators felt he would be an illegitimate champion.
In the Belmont, Forward Pass finished second by one and a quarter lengths to Greentree Stable's colt Stage Door Johnny, a horse who had not raced in the Derby or the Preakness but had been specifically bred and conditioned for competing at longer distances.
"[11] The use of phenylbutazone was subsequently approved on March 6, 1974, by the Kentucky Racing Commission in recognition of medical research that showed it does not enhance a horse's performance.