Wearing the number nine shirt, Mifsud opened his account in the sixteenth minute when he made the most of a cross by Bello Osagie.
Five minutes later the duo combined and Mifsud nipped into to score.
Birkirkara pulled one back but in the 69th minute, Mifsud completed his hat-trick with an unstoppable shot.
A late penalty gave Qormi, a victory that many would not have thought possible last week.
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