Anthony Beane and Sean O'Brien each added 10 points for the Salukis (12-20), who will play top-seed Wichita State on Friday. Thursday was the fifth time in six years Southern Illinois has played in an opening round "play-in game." They are 3-4 overall in the first round.
After Missouri State's Dorrian Williams hit two free throw to cut the Southern Illinois lead to 45-43 with 3:20 to play, the Salukis scored the next five, highlighted by and O'Brien 3-pointer, to push the back to seven and put the game away.
Austin Ruder scored 17 to lead the Bears (11-20), who shot just 35 percent from the field and turned the ball over 16 times.