In his place, a freshman: Jared Barnett.
Barnett wasn't great, finishing 16-of-36 for 180 yards and no touchdowns. But a bigger number was the zero in the interception column.
He carried the ball 13 times for 66 yards, too.
Jantz has struggled with turnovers all season, throwing nine interceptions (the most in the Big 12) to just 10 touchdowns in six games.
Barnett didn't get much help from his receivers Saturday, who struggled with drops. His top target, Darius Reynolds, had just one catch for seven yards and dropped an easy pass down the middle of the field late in the first half that likely would have led to points.
Josh Lenz, though, stepped in with a career day, catching eight passes for 117 yards for his first 100-yard day.
Jantz has to progress as a passer, but it's clear Barnett isn't far behind. Jantz is battling a foot injury as well.
Barnett made plays and kept his team in the game. Not something you would expect from a freshman playing in his first meaningful game. Who knows how Barnett will grow if the Cyclones keep him at the helm and give him his first start next week.
Jantz is a junior, but the juco transfer is playing his first season of major-college football, too.
Iowa State doesn't have a ton of firepower offensively, and it can't afford to have possessions end in turnovers, even if Jantz's fourth-quarter heroics pushed the Cyclones to a 3-0 start.
Barnett didn't turn the ball over on Saturday, and until he does, he shouldn't have to turn the job over either.