Coach Gus Malzahn announced the news on Twitter on Friday night.
Nick Marshall is not 100 percent so we are going with Jeremy Johnson at QB tomorrow. Have a lot of confidence in him and he is well prepared
— Coach Gus Malzahn (@CoachGusMalzahn) October 11, 2013
Johnson, an ESPN 300 recruit, arrived at Auburn over the summer and was one of four quarterbacks who battled for the starting job during fall camp. He is the only one who has yet to play a snap this season, but the Auburn coaches will go with him Saturday, taking away any possibility of a redshirt.
"We have not played him yet, and I know obviously it is getting to a point now where you have to do what is best for him and what is best for your team," Malzahn said earlier in the week. "But he is still getting a lot of reps in practice and he is improving, there is no doubt."
As a senior at Montgomery (Ala.) Carver High School, Johnson threw for 3,193 yards and 31 touchdowns and also ran for 705 yards and seven touchdowns. He was named Mr. Football in the state of Alabama for 2012.
Auburn might also use quarterback Jonathan Wallace at some point Saturday. He started four games for the Tigers last year, and he played sparingly in the first two games, completing one pass for 20 yards and rushing twice for seven yards.
Saturday's game between Auburn and Western Carolina kicks off at 2 p.m. ET.