Kendrick Perry led the Penguins (13-9, 5-4) with 22 points. Kamren Belin made six 3-pointers and finished with 19 points, and Damian Eargle had 13 points, 12 rebounds and seven blocked shots for Youngstown State.
The game saw 12 lead changes but the Penguins never led by more than two points.
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point guard Melo Trimble, considered a lock to leave the program before struggling in the second half last season, has withdrawn from the NBA draft and will return for his junior season.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.