With the teams tied at 1-1 in the best-of-five shootout, the Spartans called on senior captain Brendan Mageary, and he beat John Liquori stick side to give St. Mary's the 3-2 win over the Panthers.
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St. Mary's now has a chance to advance to the semifinals if it can beat St. John's Prep in the final round robin game on Sunday. But for this night, St. Mary's was able to shake off a less than stellar game.
"This is a funny game," St. Mary's coach Mark Lee said after earning his 350th victory. "We played great on Sunday and lose in a shootout. Then (Wednesday) we didn't play well at all and win. But I'm proud of how the guys kept battling."
For Mageary, who has been around the program since being a waterboy at the age of seven, seeing his team come through despite not having its best game was huge.
"We had to come out and play hard," Mageary said. "But everyone in the locker room dug deep and kept fighting."
The Spartans had a 34-26 shots advantage and two power plays in overtime but couldn't seal the deal.
In the shootout, Bobby Mullins gave St. Mary's a 1-0 lead before Panther forward Matt Foley made a sweet stop move to slide the puck through the legs of Bailey MacBurnie.
St. Mary's took the lead back when Jarrod Fitzpatrick tucked a shot past Liquori. But Frank Crinella's water-bottle shot in the fifth round tied it and shifted all the pressure to Mageary.
The senior was deliberate and made a quick fake to the right before snapping a shot stick side to end the drama.
"Brendan has been a part of this program for such a long time and for him to score that goal is such a great story," Lee said.
Things started well for St. Mary's as Cam O'Neill and Mullins scored three minutes apart to give the Spartans a 2-0 lead 5:35 in. But Peter Crinella's goal off a face-off two minutes later cut the lead to 2-1.
Cathedral then survived a 5-on-3 late in the period and used it to change the momentum.
"We didn't have our 'A' or 'B' game and that's a credit to Springfield," Lee said. "They are a really good team and it's always a battle when we play them."
The Panthers tied the game midway through the second when Cullen Geary tipped home Frank Crinella's point shot on a power play at 6:08 as they began to control the play.
Liquori and MacBurnie, however, would shut things down from there as neither team could score over the final 23 minutes of regulation and then through the 12-minute overtime session.