The Boilermakers (6-6) won their second straight to reach the .500 mark before starting Big Ten play. They barely avoided a fourth loss this season to a non-BCS conference school after an 11-day Christmas break.
Purdue struggled to put the game away until a late surge. Each time it looked like the Boilermakers were about to pull away, the Tribe came right back.
But Jacob Lawson broke a 58-58 tie with a layup with 7:46 to go, and the Boilermakers outscored William & Mary 13-8 the rest of the way.
Maryland point guard Melo Trimble has withdrawn from the NBA draft and will return to College Park for his junior season, sources told ESPN.
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.