Down 25-24 at the break, Ohio opened the second half with a 23-12 run to take a 47-37 lead with 12:18 remaining. Northern Illinois then went nearly nine minutes without scoring, allowing the Bobcats to stretch their lead to 62-40 with 3:47 left.
Kellogg was 6 of 8 from the floor and hit four of five 3-pointers. Ndour made all four free throw attempts, and grabbed eight rebounds.
Ohio (13-4, 3-1 Mid-American) has won ten of its last 11 league road games, its best in program history.
Maryland point guard Melo Trimble, considered a lock to leave the program before struggling in the second half last season, has withdrawn from the NBA draft and will return for his junior season.
Louisville's Chinanu Onuaku, who recently underwent a medical procedure to correct a heart rhythm issue detected during the combine, will keep his name in the NBA draft pool.
Andrew White III will return to the Nebraska men's basketball team next season after removing his name from the NBA draft.