The famous horse was superbly steered home by lifelong United fan Ruby Walsh, after Betfred was swamped with bets on the big race.
Betfred boss Fred Done said: “I’ve been bashed up by Kauto Star’s win, but I’ll pay out with a smile when a horse produces a performance like that.
"We’ve seen history made today by the first horse ever to regain the Gold Cup and it was a pleasure to have witnessed it, although obviously not pleasant to watch! Congratulations to Ruby Walsh and Paul Nicholls. I’ll be very careful about taking on Kauto Star again.
“It's been a roller-coaster week so far, now I just hope my beloved United win against Liverpool. I am always happy to pay out to my fellow Reds.”
Kauto Star won by thirteen lengths and was chased home by Denman ridden by Sam Thomas, another United fan.
Unfortunately Ruby and Sam can’t watch Saturday's big match because they will both be in racing action again. All the cash for the game so far is for United, with 2-0 being the most popular bet at 13/2. For more odds, or to place your bet, visit manutd.com/bet.