{v. phr.}, {informal} To bet on a certain failure; to gamble without a chance of winning. * /You bet on the New York Mets to win the World Series? Why put your money on a scratched horse?/ Compare: STACK THE CARDS.
PUT ONE'S MONEY ON A SCRATCHED HORSE
Meaning of PUT ONE'S MONEY ON A SCRATCHED HORSE in English
Dictionary of English idioms . Словарь английских идиом. 2012