What was unusual about jockey Frank Hayes' winning race at Belmont Park in 1923?

On the 4th of June, 1923, jockey Frank Hayes (1901-1923) won a steeplechase at the prestigious Belmont Park race course, near New York in the USA, riding a horse named Sweet Kiss, owned by a Miss Frayling.

His dates offer an all too obvious clue as to what happened! He suffered a heart attack and died during the race, but his body remained in the saddle, and he and Sweet Kiss were first past the post.

Nobody realised what had happened, until Miss Frayling and the race course officials came to congratulate him, and then the awful truth dawned on them. It has been suggested, though never definitively proven, that his drastic attempts to lose weight before the race may have contributed to his demise.

He was buried wearing his racing silks, and Sweet Kiss was immediately retired from racing.

To this day (September 2021) it is the only verifiable instance of a dead jockey winning a race.