Their opponents, Holy Trinity College, Cookstown - making their first ever appearance in the prestigious final - brought fans from across Mid Ulster together for the big game.
Check out more pictures from the big game:
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Holy Trinity’s Conal Devlin and St Mary's Niall O’Donnell. Picture: Matt Mackey / Press Eye.
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St Mary's fans cheer on their team. Picture: Matt Mackey / Press Eye.
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Holy Trinity’s Shane Hughes and St Mary's Ronan Walls. Picture: Matt Mackey / Press Eye.
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Action from Holy Trinity’s Shane Hughes and St Mary's Ronan Walls. Picture: Matt Mackey / Press Eye.
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