Jamie McGonigle , Jordan Allan and Brad Lyons found the net for the Bannsiders as they sealed their spot in the last eight.
McGonigle coolly slotted the Bannsiders in front with only eight minutes gone after Ian Parkhill played him in.
Jordan Allan spurned a great opportunity to double the home side’s advantage on 23 minutes, but he fired over from Darren McCauley’s cut back.
McGonigle threatened again with 28 minutes on the clock, this time though Ryan McBride tipped the shot away.
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Knockbreda should have equalised on 52 minutes, but Dylan Wilson’s lob sailed over the bar.
The Bannsiders doubled their lead on 61 minutes as Allan fired home from Parkhill’s through ball.
And right at the death Brad Lyons took adavantage of a poor back pass to wrap up the win for the Bannsiders.