Brandon Paul led Illinois (12-1) with 23 points. Tyler Griffey scored 14, Joseph Bertrand had 13 and Nnanna Egwu 12 for the Illini. Missouri used a 9-0 run late in the game to take the lead for good at 70-64. Brown led the spurt with four points.
The Tigers held a 58-35 edge on the boards and outscored Illinois 44-24 in the paint.
Illinois, which leads the overall series 20-12, won nine meetings in a row from 2000-08.