Jay Harris came off the bench to score 13 points for Valparaiso (14-7, 7-2 Horizon) and Ryan Broekhoff scored 12 and had three steals.
The lead changed hands 15 times and the score was tied on eight occasions.
Valparaiso outscored Illinois-Chicago (6-13, 2-7) 32-10 in the paint and had a 23-17 scoring advantage off the bench.
Gary Talton scored 12 points to lead Illinois-Chicago and Hayden Humes and Paris Carter each scored 11. Humes also had six assists and Daniel Barnes had three steals.
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