Verified answer

My answer is 'Sweet Kiss' whose Jockey Frank Hayes apparently died somewhere in the middle of the race, but his body remained in the saddle throughout. Sweet Kiss eventually crossed the finish line, winning by a head with Hayes technically still atop her back, making him the first, and thus far only, jockey known to have won a race after death. Sweet Kiss, instantly gained a new name: 'Sweet Kiss of Death.'  Sweet Kiss, was owned by Miss A.M. Frayling. And, yes Miss Frayling found it hard to get jockeys to ride her, no doubt due to superstition, so the mare was retired albeit with an impeccable record: unbeaten. One race. One win.

I`m making a guess.

*Bayakoa*