Bertrand's production off the bench for the No. 10 Fighting Illini (12-0) combined with another big game from guard Tracy Abrams to help Illinois overcome Eastern Kentucky guard Corey Walden's 19 points off the bench on Sunday.
Both teams' offensive attacks were held in check on Sunday, especially in the first half, which ended with Illinois up 25-20.
The two offenses came somewhat alive in the second period, with Illinois eventually building a late, 10-point lead with just more than seven minutes to go that they would not relinquish on their way to a 13-point win.
Eastern Kentucky looked like they would get back in the game after two Walden free throws pulled the Colonels to within four, but Abrams, who finished with 13 points, scored five key points in the final minutes to help Illinois escape with the win.