Kevin Cooper notched a hat trick, including the shorthanded game-winner 7:03 into the third period, as Middlebury came back from 2-0 down to win its third consecutive NESCAC championship, 3-2.
On the winning goal, Cooper broke in on the left wing and scored from what seemed to be an impossible angle low.
The Panthers will receive an automatic bid to the NCAA Tournament when the pairings are announced on Sunday night. Trinity will hope for an at-large bid.
Middlebury was controlling much of the first period play until Trinity got on the board first at the 15:52 mark. Joseph Ori had some space behind the net and found Jeffrey Natale just outside the crease for the quick redirect into the net.
The duo connected again just 2:21 later as Natale broke in with some room after a feed from Ori and slide it across the crease and into the net.
The Panthers faced a tough Geoffrey Faulkner in goal. He stopped all 16 shots as the Panthers outshot Trinity 16-5 in the period.
The Panthers got on the board just 18 seconds into the second period on the power play as Matt Dunn streaked down the right wing and hit Kevin Cooper with a great crossing pass for the one-time goal.
With just 1:07 left in the period, Cooper picked up a rebound after a Dunn shot and jammed it through the pads of Faulkner to even the game at two.
The Panthers held a 27-12 shot advantage after two periods. Trinity threatened with its goaltender pulled late, but could net get the equalizer.
Christian Carlsson made 12 saves in goal for Middlebury, while Faulkner stopped 35 for Trinity.