Seven-foot freshman center Kofi Cockburn scored 11 points and grabbed nine rebounds for Illinois (8-3), narrowly missing his seventh double-double.
A.J. Oliver II led Old Dominion (3-8) with a game-high 17 points. Xavier Green added 13 points for the Monarchs.
Illinois guard Da'Monte Williams left the game midway through the first half with what appeared to be a separated shoulder. Williams, in obvious pain, was taken to the locker room and returned to the game a few minutes later after receiving medical attention.
The Illini led 40-25 at the half, holding the Monarchs scoreless the final 3:21 before the break. Illinois opened the game with a 7-0 run and led 13-4 less. Cockburn was everywhere, blocking shots on one end and dunking the ball on the other. The big man had nine points and three rebounds at the break.
ON THE RUN
Illinois opened the game with a 7-0 run and another 6-0 spurt before the half. The Illini also ripped off a 7-0 run early in the second half to widen the lead to 51-32 with 10:55 left.
"We had a few mental lapses, which we'll work on in practice," said Illinois coach Brad Underwood. "But overall, I'm happy with our guys' performance."
THE BIG MAN
Cockburn, the reigning Big Ten Freshman of the Week, recorded his sixth double-double in Wednesday's upset win over No. 3 Michigan, posting game highs of 19 points and 10 rebounds while blocking a career-high four shots. With that effort in just 10 games, Cockburn has already equaled the Illinois record for double-doubles by a freshman, first set by Efrem Winters during the 1982-83 season.
Cockburn, along with most of the starters, was pulled from Saturday's game with about four minutes left in the game to allow non-starters to get some playing time, or he would have likely had another double-double.
Old Dominion: Acquitted itself nicely against a bigger and more athletic Big Ten Conference foe but couldn't overcome a typically fierce Illinois defense.
Illinois: Did what it had to do, winning a game it should have won and overcoming what might have been a hangover after defeating No. 3 Michigan on Wednesday.
Old Dominion travels to Richmond on Wednesday.
Illinois plays another non-conference game at Missouri on Dec. 21.
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