Question: Which Racehorse was the daughter of the American Thoroughbred was the unofficial 1920 American Horse of the Year, considered one of the greatest racehorses of all time?
Sentence (from "Bateau (horse)"): Bateau (born 1925) was an American Thoroughbred Champion racehorse and a daughter of Man o' War and out of the French mare Escuina.
Relevant evidence: Yes