One of the harder fastballs in the game, Kopech can call himself a flamethrower. He touches the zone a bit too often allowing solid contact with a .289 ISO.
Kopech’s slider has some room to improve. For his main breaking and offspeed pitch, he allows too much contact, especially contact in the air, to be an effective pitch with two strikes.
Playing well off his fastball in both movement and velocity, Kopech’s changeup generated a decent whiff rate. Additionally, he kept the ball down when hit, never allowing a fly ball in the few batted balls against it.