GRAETTINGER - Graettinger-Terril/Ruthven-Ayrshire gave North Union a tougher battle in the teams' second meeting on Friday.
But the Warriors gradually pulled away throughout the night for a 48-28 win.
North Union won the first game between the two schools, 62-20 on Dec. 7.
"This was a hard-fought battle," said North Union coach Merle Tigges. "We had an eight-to-10 point lead most of the game and finally pulled away at the end. GTRA really stepped up their defense."
North Union led 12-7 after one quarter, 22-14 at the break and 34-23 after three quarters.
"Defensively we played a pretty good game for the most part," said GTRA coach Todd Hough. "Offensively their pressure bothered us and we just didn't get many looks at the basket."
Aurora Oliver led North Union with 14 points and three rebounds. Cheyanne Boland scored 10 points, Madison Bollig and Maddy Irmiter each had eight points, Jasmine Clausen had five points and Sara Rolling had three.
Clausen also had five rebounds and five steals and Dena Looft had six rebounds.
For GTRA Marly Bakken was 4-for-6 from the field and finished with 10 points. Grace Skattebo had eight points and nine rebounds. Brooke Hoffman finished with five points while Cassy Hampson and Morgan McGrauth each had two and Emily Moran had one.
McGrauth had three assists and Hampson had two steals.
North Union (10-5 overall) hosts Clay Central-Everly on Tuesday.
GTRA (4-11 overall, 3-5 in the conference) is on the road against Marcus-Meriden-Cleghorn today.