Alyssa Chipelo, who led a Dobbs Ferry comeback victory over the No. 1-seeded Bulldogs with 21 points, passed the ball to Sheridan for the go-ahead basket.
The upstart fourth-seeded Eagles will meet Woodlands (No. 7 seed) in Saturday's championship game at noon in the County Center.
Irvington led 18-5 after and 32-19 at halftime before the Eagles used a tight defense and cut the Bulldogs lead to 38-33 after three quarters. The teams were tied 44-44 at the end of regulation time.
Dobbs Ferry led 49-44 after the first two minutes of overtime but Laurilyn Gelardi scored 8 points to help the Bulldogs take a 52-51 lead with 20 seconds remaining. Gelardi finished with 21 points.
Molly Althoz had 16 points for the Eagles and Sheridan scored 12.
Section 1 Championship Week Semifinal Schedule
Wednesday, Feb. 26 Class A girls semifinals: No. 2 Albertus Magnus vs. No. 3 Rye, 3 p.m. Class A boys semifinals: No. 2 Panas vs. No. 6 Tappan Zee, 4:45 p.m. Class A girls semifinals: No. 1 Beacon vs. No. 4 Peekskill, 6:30 p.m. Class A boys semifinals: No. 1 Eastchester vs. No. 4 Harrison, 8:15 p.m.
Thursday, Feb. 27 Class AA girls semifinals: No. 3 Clarkstown South vs. No. 7 Mahopac, 3 p.m. Class AA girls semifinals: No. 1 Ossining vs. No. 4 Horace Greeley, 4:45 p.m. Class AA boys semifinals: No. 2 Clarkstown South vs. No. 6 Spring Valley, 6:30 p.m. Class AA boys semifinals: No. 1 Mount Vernon vs. No. 5 Mahopac, 8:15 p.m.
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