The Knights play Section 4 champ Union-Endicott on Saturday at 2 p.m. at Binghamton University with the winner moving on to the Class AA Final Four in Glens Falls.
Mount Vernon led by a slim 32-26 at halftime but extended the lead to 51-40 after three quarters and moved away from Newburgh in the fourth.
Judah Alexander had 10 points and 8 rebounds and Tyger Hackett and Yhanni Bartley each added nine points for the Section 1 champion Knights, who have won 15 of the last Section 1 titles.
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