The Crimson (15-5, 5-1) held Yale to just 11 points and three field goals in the first half - the fewest allowed under coach Tommy Amaker.
But Harvard scored only 16 by halftime and Yale (16-7, 5-1) closed quickly when Javier Duren nailed a 3-pointer to open the second half. A Jack Montague trey pulled Yale to 50-48 with seven seconds left. Harvard called time and Saunders went to the line for the foul shots that iced it.
Harvard collared 32 defensive boards and outrebounded Yale 42-32.
Duren surpassed 1,000 career points with a 3-pointer with 1:07 left. Montague scored 11.