The Phoenix were without leading scorer and Horizon League player of the year Keifer Sykes, who hurt his left ankle in the conference semifinal loss on March 8 and was a scratch just before this game.
It was apparent Green Bay was missing its floor leader, committing a season-high 21 turnovers. While the fourth-seeded Phoenix were giving up the ball, the fifth-seeded Bruins gradually built their lead.
Belmont (25-9) had a slim 37-33 first-half advantage before ending the half on a 12-4 run to go up 49-37. The Bruins increased the lead to 58-39, and Green Bay (24-7) got no closer than seven late in the game.
Greg Mays scored 15 points to lead Green Bay.