Under the pseudonym "Redstone Stable", Rothstein owned a racehorse named Sporting Blood, which won the 1921 Travers Stakes under suspicious circumstances. Rothstein allegedly conspired with a leading trainer, Sam Hildreth, to drive up the odds on Sporting Blood. Hildreth entered an outstanding three-year-old, Grey Lag, on the morning of the race, causing the odds on Sporting Blood, to rise to 3–1.