Kansas State quarterback Avery Johnson has been ruled out for the Wildcats' game against Arizona State, sources told ESPN's Pete Thamel on Saturday.
Backup Jacob Knuth is expected to make his first career start against the Sun Devils (3:45 p.m. ET, ESPN2). The Minnesota transfer has played in seven games over his four seasons in the program.
Johnson was downgraded to doubtful in the Big 12 availability report on Friday after suffering an injury last week in a 35-24 win over Kansas last week. Kansas State hasn't specified the extent of the injury, but Johnson acknowledged experiencing some shoulder pain in his postgame interview.
The three-year starter ranks fourth in the Big 12 in total offense this season with 1,301 passing yards, 462 rushing yards, 13 total touchdowns and three interceptions.
Kansas State backup Blake Barnett was still listed as questionable on the Big 12 availability report on Friday.
Knuth will face a fellow backup in Arizona State's Mikey Keene. The former UCF, Fresno State and Michigan quarterback replaced Cutter Boley in the second half of a loss to Texas Tech last week and will start Saturday.