Cairah Green hit a 3-pointer at the buzzer to give Zachary a 40-37 win over Walker in District 4-5A action Tuesday at Zachary.
The basket was Green's only one of the night and the Lady Broncos' on trey of the game.
Walker, which came in as the No. 2 team in the Class 5A power rankings, trailed 13-4 at the end of the first quarter cut the lead to 19-18 at halftime before tying the game at 29-29 heading into the fourth quarter.
Caitlin Travis led Walker, which went 11-for-19 at the line, with 17 points, while Ja'Miya Vann added nine and Lanie Miller had seven, six in the second quarter.
Alissa O'Dell led Zachary, No. 8 in the 5A power rankings with 12 points, while Kali Howard had 10.