The Green Knights (22-6-1) were making their 11th Frozen Four appearance but fell short of a fifth NCAA Championship.
The Green Knights pulled their goalie with 1:38 left but couldn’t get the puck past Trinity goaltender Alex Morin, who made 31 saves, including stopping all 13 shots he faced in the third period.
Jeremy Olinyk opened the scoring in the first period, scoring his seventh goal of the season. Trinity would score twice to go up 2-1 before Pijus Rulevicius tied the game 2-2 with a second period power play goal.
The Bantams scored the games final goal at the 18:26 mark of the second period to go up 3-2.
Trinity outshot St. Norbert 37-33. T.J. Black made 34 saves in goal for the Green Knights.