Briar Woods Coach Charlie Pierce is known for his attention to detail and preparedness when his team takes the field on Fridays.

But Pierce missed a beat this week when the No. 4 Falcons neglected to go over their overtime script.

Faced with a double-overtime thriller against cross-town rival Broad Run in a Virginia 5A North region semifinal Friday afternoon in Ashburn, the Falcons ditched the script, relied on their veteran defense and kept the ball in the hands of their most experienced player.

After the Falcons forced Broad Run to kick a field goal on its second overtime possession, senior quarterback Trace McSorley scored on a keeper up the middle to lift Briar Woods to a 37-34 victory and extend the Falcons’ season to next week’s region final.

“Our team had a lot of heart to stop them in overtime,” said senior Melvin Holland Jr., who made several key plays at wide receiver and linebacker down the stretch. “Our heart brought us through this one.”

The Falcons survive at home against the Spartans and advance to the Virginia 5A North region final. (Andrew Kloc for Synthesis/Koubaroulis LLC./The Washington Post)

Briar Woods will face the winner of Saturday’s game between top-seeded Massaponax and North Stafford — which dealt the Falcons their lone loss this season.

The Falcons (12-1) scored touchdowns on their first two possessions and took an early 17-0 lead, but on their first drive of the second quarter McSorley took a big hit to his right hip that forced him out of the game.

“I tried to make a move to get some extra yards, and I felt a helmet hit the top of my hip, and I felt my whole right side lock up,” said McSorley, who improved to 54-4 in his four years as a starter. “The trainer did a great job putting heat on it to loosen it, and he gave me a lacrosse shoulder pad to cushion hits to my hip.”

McSorley (294 passing yards, two touchdowns) returned on the next series but was clearly still favoring the hip. With his mobility limited, the Falcons’ potent offense stalled.

Briar Woods led 24-10 at the half, but three third-quarter turnovers — including a fumble on the Broad Run 4-yard-line — enabled the Spartans to get back into the game.

No. 18 Broad Run (9-4) scored 14 unanswered points in the third quarter as Brady Reitzel connected with Chuck Davis and Travis Fulgham for touchdowns of 27 and 87 yards, respectively. Reitzel threw for 180 yards and three touchdowns.

Both teams scored passing touchdowns on their opening overtime possessions, but Briar Woods forced a Sammy Sergei 27-yard field goal on the Spartans’ second overtime possession.

Broad Run's Chuck Davis, left, catches a third-quarter touchdown pass aganst Briar Woods. The score helped the Spartans rally to tie the game and force overtime, but Briar Woods prevailed, 37-34. (John McDonnell/The Washington Post)

McSorley hit Brandon Polk at the 3-yard line, and two plays later, the Vanderbilt recruit powered into the end zone to give the Falcons their 18th consecutive playoff victory and continue their march toward a fourth consecutive state championship.

“He’s unbelievable,” Pierce said of McSorley. “He got injured early on, and he sucked it up.

“People always ask me what’s going to happen next year. I told them ‘I ain’t worried about next year. I’ll ride No. 7’s coattails as far as I can.’ ”