Oklahoma State starting quarterback Spencer Sanders will miss the team's season-opening game against Missouri State because the redshirt junior is in COVID-19 protocols, multiple sources confirmed to CBS Sports. The Cowboys are expected to start sophomore Shane Illingworth in his place.

Sanders is entering his third year as the starter for coach Mike Gundy with 20 combined starts in his last two seasons. A former four-star prospect who earned Gatorade Player of the Year honors in Texas as a high school senior, he made nine starts last year and finished his season as the Cheez-It Bowl MVP in a win over Miami.

Illingworth appeared in four games and made two starts last season as a true freshman while Sanders dealt with various injuries. In those appearances, he completed 41 of his 70 pass attempts for 554 yards to go with four touchdowns and one interception. OSU went 3-1 in those games, with his lone loss coming against then-No. 18 Oklahoma in the annual Bedlam rivalry. A 6-foot-6 signal-caller, Illingworth was the highest-ranked signee of OSU's 2020 recruiting class as a four-star recruit out of California. 

It is unclear when Sanders will be cleared from COVID protocols, but it could potentially put his availability in jeopardy for OSU's Week 2 game against in-state foe Tulsa. OSU faces Boise State the following week on the road in a primetime showdown that could potentially serve as Sanders' season-opener if he's not able to return by next week. 

The Cowboy Radio Network first reported Sanders' absence.