The Crimson took sole possession of first place in the Ivy League with the win.
Will Walker scored two of his game-high four goals during the run after a 6-all halftime score. John Hogan (St. Mary's) led the Big Red (9-1, 3-1) with three goals.
Harvard (6-4, 3-0) can clinch a spot in the Ivy League tournament with one victory in its final three conference games.
"I give all the credit to my teammates," Class said.
Duke extended its winning streak to six games; it owns a share of the top spot in the conference standings with No. 6 Maryland.
Steve Pontrello tied the score at 10, setting up Keenan (Boys' Latin), who won the faceoff and scored five seconds later.
Saint Joseph's 9, No. 11 Bryant 7: The host Hawks (8-3, 4-0 Northeast Conference) finished strong with a 3-1 run in the fourth quarter to upset the Bulldogs (9-3, 2-1).
No. 12 Fairfield 9, Michigan 8: Drew Federico scored his second goal to give the Stags (9-2, 2-0 Eastern College Athletic Conference) a 9-7 lead with 2:12 left as they held on to beat the host Wolverines (4-8, 1-2).
No. 13 Penn 10, No. 15 Brown 8: The host Quakers (5-3, 2-2 Ivy) broke a 7-all tie by scoring three straight in the fourth quarter to beat the Bears (6-4, 1-2). Kylor Bellistri had three goals for Brown. Penn had a two-goal efforts from Nick Doktor, Pat Berkery and Alex Blonsky.
No. 14 Army 8, Boston University 7: The Black Knights (7-3, 5-1 Patriot League) went up 8-4 with 14:36 left in the game and withstood a 3-0 rally by the host Terriers (1-9, 1-5).
John Glesener led Army with two goals and two assists.
No. 17 Yale 16, Dartmouth 10: Shane Thornton had three goals as the visiting Bulldogs (6-3, 2-2 Ivy) won their second straight. The Big Green (1-6, 0-3) led 3-2 after the first quarter, but Yale went on a 4-0 run to close out the half.
No. 3 Syracuse 18, Virginia Tech 4: The visiting Orange (12-1, 4-1 ACC) jumped out to a 14-1 lead at halftime and was never threatened. Meghan Macera (Westminster) scored twice for the Hokies ( 7-6, 0-4).
No. 4 Boston College 13, No. 9 Duke 11: Covie Stanwick (Notre Dame Prep) and Sarah Mannelly each scored five goals to lead the Eagles (10-3, 2-3 ACC) past the host Blue Devils (8-5, 2-3).
Jessica Roach had four goals for Vermont.
No. 20 Virginia 13, 8 Notre Dame 8: Liz Colgan (Notre Dame Prep) made 16 saves to anchor a tough Cavaliers defense that held the Fighting Irish (8-5, 1-4 ACC) to one goal in the first half.
Kelly Boyd (St. Paul's) and Maddy Keeshan each had three goals for Virginia (7-6, 1-3).