Notre Dame (27-3, 9-1) took a 25-11 advantage at the intermission but had to hold off a late charge as North Vermilion outscored the Lady Pios 25-16 in the second half.
Notre Dame also struggled from the free throw line, going 12-of-28 on the night. They were 8-for-21 in the second half alone.
Alex Miller paced the Lady Pios with nine points while Lexie Trosclair added eight and Taylor Simon scored seven. Kylie Pannell followed with six points; Marie Ledet scored five; Mary Charles had four and Mallory Chiasson scored two.
Over in Erath, the Pios went on an 18-10 run in the fourth quarter and walked away with a 59-47 victory over the host Bobcats.
The Pios (12-14, 4-4) trailed 15-14 in the first quarter before rallying in the second frame to take a 26-25 edge at the half.
BJ Vidrine and Drew Trahan each hit 3-pointers in the third quarter and Stu Cook addded four points to help the Pios extend the lead to 41-37 heading into the final stanza.
Kane Thibodeaux and Ricky Stoma took over in the fourth quarter, combining for 13 points to help preserve the victory.
Vidrine, who connected on four 3-pointers, and Jeremy Smith led the Pios with 12 points each. Stoma also hit double figures with 10 points.
Cook followed with nine points and Thibodeaux added eight. Trahan and Jacob Rogers rounded out the Pios’ offense with four points each.