Markle scored a game-high 21 points on seven-of-twelve shooting, including five-of-nine from behind the three-point arc. Fellow junior Megan Cevasco also had a hot hand, as she scored 18 points on eight-of-twelve shooting and grabbed eight rebounds.
Both Markle and Cevasco opened the game with three-pointers to give the Polar Bears an early lead.
At the 13:45 mark in the first half, a lay up by sophomore Alisha Rinehart ignited a 17-2 run, capped by a jumper by Leah Zimmerman, giving ONU a 35-11 lead with 4:30 remaining in the half.
The Polar Bears would take a 35-18 advantage in the locker room.
In the second half, Northern continued to build its lead. With 13:30 remaining, Tara Butler canned a jumper that started the Polar Bears on a 25-6 run to put the game away. Markle made a pair of free throws to cap that run and give ONU its biggest lead of the game at 65-34, with 3:48 left.
ONU shot 44 percent (25-of-57) from the floor compared to just 36 percent (18-of-50) for Adrian. The Polar Bears also held a 34-28 rebounding advantage.
Senior Danielle Andreasen also scored in double-figures for ONU with 12 points and eight rebounds. Anita Stamp was the only Bulldog to reach double-figures with 11 points.
The Polar Bears return to action on Saturday when they travel to Marietta to open OAC play at 3 p.m.