At Ellsworth, Josh Bean scored the first goal of the game on a direct kick, then added the fourth goal early in the second half to power the top-seeded Eagles to victory.
Jack Weeks headed in a Bean corner kick in the first half to give Ellsworth (14-1) at 2-0 lead, then Maks Grover (unassisted) and Bean (corner kick off goalkeeper) scored 37 seconds apart in the first two minutes of the second half to make it 4-0.
Steven Mahon made 4 saves on 6 shots.
Christian Williams scored a second-half goal, assisted by Jacob Levangie-Thompson, for No. 8 Belfast (9-5-2). Sam Kulikowski and Tremmil Groene made 15 saves on 25 shots.