Tuioti-Mariner spun Falk around and threw him to the ground for a 9-yard loss, with the redshirt sophomore's head violently hitting off the Rose Bowl turf. Falk was unable to get to his feet, trying to crawl off the field before trainers and team doctors rushed out to attend to him.
Falk went through several simulated dropbacks on the sideline before a Washington State official took away his helmet and began ushering him back to the locker room.
Falk was replaced by Peyton Bender, a redshirt freshman who had attempted just six passes while appearing in two games this season.
Falk had completed 17 of 20 passes for 137 yards before exiting on Saturday night.