If No. 18 Baylor is going to continue their remarkable pursuit of a Big 12 title in 2019, they’re going to have to do it without their best defensive player.

A school official confirmed to the Dallas Morning News on Sunday that senior linebacker Clay Johnston will miss the rest of the season after injuring his knee in the Bears’ double overtime victory over Texas Tech on Saturday.

The news is a huge blow to Matt Rhule’s defense, which was tops in the Big 12 in a number of statistical categories and the No. 17 scoring defense nationally.