The Lady Pirates forced overtime, then went on to a 38-36 win.
Perkins outscored the hosts 12-6 in the fourth quarter.
Willard had a chance to win in the last minute but missed two at the free-throw line.
Perkins missed a potential game winner with with under 10 seconds left.
The Lady Pirates then tallied two points in the overtime for the win.
Kayla Yost cut left to right across the lane and hit a runner from 10 feet for Perkins’ points in overtime.
Willard’s Olivia Bauer hit the rim from 30 feet as time expired.
Yost paced the Lady Pirates with 14 points and Abbey Seeholzer added 11.
Hannah Schloemer led the Lady Flashes (10-6) with nine points and Gabi Baldridge added eight.
Read more in Wednesday's Sandusky Register and Norwalk Reflector.