With the score tied and neither Centreville nor South County willing to relinquish control of Friday’s back-and-forth Virginia 6A North region quarterfinal, Centreville elected to go for it on fourth down.

But just before the pivotal snap, Taylor Boose flinched in the backfield, resulting in a five-yard penalty that placed the Wildcats seven yards away from the first-down marker.

As the sideline and crowd groaned, Centreville quarterback Scott Walter grabbed Boose by the helmet and exhorted him to shake it off, that neither this game nor the No. 2 Wildcats’ undefeated season would be extinguished with one miscue.

Boose nodded and after taking his spot with the punt team, the junior made amends by rumbling 32 yards on a fake punt for what would be the decisive touchdown in a 55-35 win in Centreville.

With the victory, the Wildcats (12-0) advanced to host Stonewall Jackson, which upended Langley, 51-48, in next Saturday’s region semifinals.

Before Friday, Centreville had not trailed by more than seven points nor at halftime.

Midway through the second quarter, however, the Wildcats found themselves down 21-0 as South County (9-3) piled up 262 first-half rushing yards behind its triple-option offense.

The Stallions’ defense proved just as efficient, holding Centreville’s high-octane attack without a first down for the opening 15 minutes.

The Wildcats gained some traction just before halftime, thanks to Walter.

The senior lofted a pinpoint, 44-yard touchdown pass to Charles Tutt before connecting with AJ Turner for a 57-yard score to cut the halftime deficit to 21-14.

“We were still confident at halftime that we would come back,” said Walter, who had 235 total yards and three scores. “Coach [Chris Haddock] did a good job of helping us put the first half behind us because no one reads the first-half scores in the paper, anyway.”

Walter turned that confidence into a 31-yard touchdown run to open the third quarter; it tied the game at 21.

From there, the game hung in the balance. David Symmes paced the Stallions with shifty runs off the edges and Turner used his speed to break off several long catch-and-runs.

When Symmes hit Az Murphy for a nine-yard touchdown on a fake field goal to put South County up 35-28, it threatened to deflate a Centreville squad that had given up three scores on fourth down.

Instead, the Wildcats were invigorated.

The defense penetrated into the backfield to force three South County fumbles while Turner and Boose rushed for two touchdowns each to secure the thrilling win.

“It took a lot of heart because most teams would have packed it up and been done after being down 21 points,” said Turner, who totaled 207 yards and four touchdowns. “But we know if you refuse to give up, you always have a chance and we took that chance and got a big win.”