Cornersville held a 29-26 lead late in the fourth quarter, before the Lady Raiders (1-6, 1-0) tallied the next four points to pull ahead 30-29 with 10.5 seconds left.
Lady Bulldog guard Brooke Holt then hit one-of-two free throws with one second left to send the game into overtime tied at 30-30, but Richland outscored CHS 10-7 in the extra session to escape with the three-point victory.
Cornersville was never able to get into an offensive rhythm and shot just 33 percent from the field overall, which included a 3-of-16 effort from three-point range, while hitting only 6-of-13 free throws.
The Lady Bulldogs did outrebound Richland 32-27 and held a 10-9 edge on the offensive glass, but offset their advantage on the boards by committing 22 turnovers.
"I don't think we played any differently than we have so far this year. From the exterior we look like a team, but when you look inside we don't have any fire. We had too many turnovers, missed layups and missed free throws tonight," said CHS coach Micah Landers. "I don't want to be completely negative because we do have some kids that are doing some good things, but we're not on the same page right now."
The Lady Raiders, meanwhile, mustered just 12 field goals on 28 percent shooting and made only 2-of-11 attempts from beyond the arc, but hit 14-of-23 free throws and committed 14 turnovers.
Center Kaitlyn Rogers led Cornersville with 13 points on 6-of-12 shooting to go along with two blocked shots. Brittany Umbles posted a double-double and tallied 10 points, 12 rebounds, six steals, and two blocked shots, while Ashley Warren and Makenzie Hopkins added four points apiece with Warren pulling down six rebounds. Martha Jane McMasters, Tiffany Skeen, and Brooke Holt rounded out the scoring for CHS with three, two, and one point respectively.
Kaylin Stacey paced Richland with 13 points, while Crystal Radford followed with nine points. Ashton Edwards and Shelby Allen both notched seven points apiece for the Lady Raiders as well.
The Lady Bulldogs held a 7-2 lead late in the first quarter thanks to three layups from Rogers and a Warren free throw, before Richland rattled off seven straight points to pull ahead 9-7 early in the second period.
After closing the second quarter with a 9-3 run on the strength of four points from Umbles and a Rogers three-point play to take a 16-13 lead into halftime, CHS outscored the Lady Raiders 8-6 through the first 6:09 of the third with the help of four points apiece from Rogers and Hopkins to open up a 24-19 advantage.
Richland used a 7-2 spurt to knot the game at 26-26 midway through the fourth period before Warren drilled a trey from the left corner to give Cornersville a 29-26 lead with 2:49 left.
Edwards then made four straight free throws to put the Lady Raiders up 30-29, but Holt was hit by Radford while attempting a jumper in the waning moments of regulation and sank the second of two foul shots to tie the game at 30-30 at the end of the fourth quarter.
In overtime, Richland opened the extra session with an 8-2 run to seize a 38-32 lead before McMasters nailed a three to narrow the gap to 38-35 with :32 left.
After Edwards hit two free throws to make it 40-35, Umbles scored on a layup to trim the deficit to 40-37 with 2.8 seconds remaining.
Rogers then intercepted the Lady Raiders inbounds pass at midcourt, but missed a long desperation heave at the buzzer.