Walker also scored the SaberCats' first touchdown in overtime, on a pass.
But it was the defense that made the difference in the end, coming up with the big stop and forcing a pair of first-half turnovers inside their own 20 to end Westmoore scoring chances.
“Our defense is where it's at,” Henderson said. “They're the heart and soul of this team, and they bring the adrenaline for the rest of us.
“They showed that tonight.”
Westmoore (1-1) had been mostly penalty free throughout regulation while Southmoore (2-0) struggled with hold after hold, racking up 138 yards in penalties by the end of the night.
But the SaberCats were mostly clean in the overtimes, while five of Westmoore's seven penalties came after regulation.
“Penalties and turnovers killed us,” Westmoore coach Billy Langford said. “We've got to learn to take care of the ball.”
Westmoore trailed 21-7 in the fourth before coming back, finally tying it on an 11-yard touchdown pass from Jhames West to Lexus Lee with 1:34 remaining to send the game to overtime.
Brickman kept the faith even when it looked like Southmoore was an extra point away from being done.
“I didn't want to call my timeout there because I wanted to save it for offense,” Brickman said. “Anything can happen, and I knew we could block the kick or force them to miss it.”