Ally Day had nine points and eight rebounds in the fourth quarter as Gardiner rallied to upset Leavitt 57-51.
Day finished with 17 points and 22 rebounds. Gardiner (12-4) trailed 39-32 after three quarters but went 7 for 7 from the foul line and 9 for 15 from the floor while outscoring the Hornets 25-12 in the fourth.
Kylee Granholm added 13 points and four steals for Gardiner.
Kristen Anderson scored 26 points for Leavitt (13-3).