Kensey Edwards scored 18 of her 23 points in the first half helping North Andrew jump out to a 26-15 lead at the break. Mercer clawed back, and took the game to overtime tied 52-52.
North Andrew (28-2) scored the first nine points in the extra period, and hung on to win the game 64-56.
Senior Danielle Chambers scored 18 points in the win.
The Cardinals move on to face Chadwick at noon Thursday inside Mizzou Arena.