Kalia Johnson scored 33 points and had six rebounds and five assists to lead Thomas Dale past No. 1 seed Cosby in the quarterfinals of the Central Region tournament.
The Knights, the Central District second seed, led by six at halftime but outscored the Titans 22-9 in the third to head into the final period up 19.
Cosby (20-7) rallied in the fourth quarter but just did not have enough as Thomas Dale prevailed by three points.
Alyssa Frye scored 19 points for the Knights and Andrea Hobbs had 10 points, six rebounds and two assists.
Andrea Bertrand led the Titans with 23 points, while Jazmin Pitts scored 17 and Becca Wann had 16.
Thomas Dale (21-5) will now face Mills Godwin (24-3) on Friday at 6 p.m. at the Siegel Center in the semifinals. The Eagles defeated Highland Springs 54-28 to advance.