The upper cut is what sealed the deal. But canelo's left hook to the liver is what really set everything up for him. It was the first punch he threw in the fight. And he peppered Billy with it every round.
Once he had Billy fearful of it he would feint to the body and make Billy lower his gaurd. Then come up top with the uppercut.
By the 8th round that liver shot had Billy's legs completely shot. The last exchange before the final uppercut Billy looked like he could barely stand. He threw a weak left and fell forward onto canelo completely exhausted. That's when canelo knew it was time to go for the kill.
Chess not checkers
....Canelo was setting up that knockout punch from the opening bell. Completely broke Billy down mentally.
There's really levels to this shyt