The lead changed hands four times in the fourth quarter, but Kirk’s TD made it 40-35, and the Bobcats’ Steven Bethley intercepted a pass to set up Rory Perez’s 45-yard field goal with 31 seconds left. Kirk finished with 105 yards on 30 carries.
Tanner Bleskin caught 10 passes for 180 yards for Montana State (3-0).
Brady Attaway threw for 418 yards, a career high, and three touchdowns for Stephen F. Austin (1-2), with Cordell Roberson accounting for 10 receptions, 163 yards and a TD. Montana State held the Lumberjacks to 55 yards rushing.
Montana State’s DeNarius McGhee threw for 275 yards and two touchdowns.