A person who talks a big game and runs their mouth with trash talk before and after a game, trying to mask their softness and lack of grit. Despite all the hype, a "Sawyher" can never actually beat their rivals and ends up losing every time. When they inevitably lose the big game to their daddy, they turn into a sore loser, sulking, whining, and making excuses like a crybaby.
"Yo, stop being a Jack Sawyer. You talk all that trash, but can't even beat your main rival."
"Man, #33 went full Jack Sawyer after getting curb-stomped by Michigan".