Oklahoma State stopped Missouri State twice on fourth down during the last two minutes of the fourth quarter to hold on for a 23-16 victory on Saturday.
The Cowboys botched a kickoff return deep in their own territory after the Bears scored their first touchdown with 3:06 remaining. Missouri State, trailing by seven, had one more chance to tie the game after its late turnover on downs but failed to complete the rally.
Oklahoma State backup quarterback Shane Illingworth threw for 315 yards and was 22-of-40 passing in his third career start.
Illingworth, who replaced regular starter Spencer Sanders in the team's season opener, raced Oklahoma State down the field on its first offensive possession and connected in the end zone with Tay Martin, who finished with 107 yards on six catches.
Connecting you to your favorite North Texas sports teams as well as sports news around the globe.
Oklahoma State's offense never looked the same, however, after its opening drive.
The Cowboys' rushing attack struggled to build rhythm, recording just 1.9 yards per carry against their FCS visitor, while Illingworth's accuracy declined from a 65.2% first-half completion percentage to 41.2% in the final two quarters.
Missouri State's defense forced two turnovers, as well as a first-half turnover on downs. The Bears' offense failed to take advantage, settling for field goals on three possessions that ended deep in Oklahoma State territory.
On a day where Big 12 powers Oklahoma and Iowa State won but struggled against heavy betting underdogs, the Cowboys went through a similar Week 1 challenge.
The Cowboys, who sit just one spot outside of the Associated Press Top 25, were without Sanders and defensive end Trace Ford, among others. The team will also be without safety Tre Sterling for the first half of its game against Tulsa after he picked up a fourth-quarter targeting penalty on Saturday.
Oklahoma State: The Cowboys appeared on their way to a rout before sputtering too often on offense and allowing the Bears to stay competitive late into the second half.
Missouri State: The Bears' defense kept the Oklahoma State offense in check for nearly all of the last three quarters but the offense couldn't cash in on the chances it was afforded.
Oklahoma State welcomes instate rival Tulsa to Stillwater on Saturday.
Missouri State opens its home slate with Central Arkansas on Saturday.
Click here to listen to the newest episode of Big Game Friday Morning.