When DeMatha Coach Elijah Brooks sends senior Cameron Phillips to line up in the secondary, he knows the Virginia Tech recruit has minimal experience reading defenses. After all, most of Phillips’s practice time is spent honing his skills as the team’s primary wide receiver.

Through the first three quarters of DeMatha’s game against Good Counsel on Friday, Phillips found himself studying the Falcons’ offense, analyzing the perfect moment for him to jump the passing lane. That opportunity came in the third quarter with DeMatha backed up on its 5-yard line and Good Counsel facing a fourth down.

As Good Counsel’s quarterback threw the ball, Phillips read the route and soared high to snatch the interception before racing 97 yards for a touchdown. The play deflated the seventh-ranked Falcons, who struggled to generate offense all night, and sparked the top-ranked Stags to a 21-0 win in Landover.

“I figured they would go to something they had done before, so when I saw the running back leak out of the backfield, I knew what was coming,” said the 6-foot-2, 184-pound Phillips. “After that, I saw all this green and just made sure I beat the quarterback down the field.”

The win snapped DeMatha’s four-game losing streak in the series and marked the Falcons’ first shutout loss in at least 13 seasons. Good Counsel (3-3, 0-2 Washington Catholic Athletic Conference) has lost its first two conference games for the first time in more than a decade following a loss to No. 10 Gonzaga last week.

The Stags talented senior class hopes to finish their careers by taking the title Good Counsel has held for four years. (Nathan Bickell for Synthesis/Koubaroulis LLC./The Washington Post)

With Good Counsel sophomore quarterback Andres Castillo making his first start, the Stags’ defense brought consistent pressure to force Castillo to rush his passes. The blitzing also slowed the Falcons’ rushing attack, which gained just 95 of the team’s 149 total yards on the night.

“We just tried to close those gaps before they could open wider at the line and make them have to pass more than they maybe wanted to,” DeMatha defensive end Deonte Holden said.

Good Counsel’s defense also put together a solid early effort, holding bruising rusher Taiwan Deal to 36 first-half yards, though the Stags (5-1, 2-0) hurt their own cause with 12 penalties.

But DeMatha’s ability to execute big plays quickly shifted the momentum in its favor. Following a 75-yard bomb from John Lovett to Chris Jones in the first quarter, Lovett found Lorenzo Harrison on a nine-yard reception for the game’s first score.

Good Counsel’s best opportunity to score came in the third quarter, when a shanked DeMatha punt placed the Falcons on the DeMatha 30-yard line. Several Perry Stefanelli runs pushed Good Counsel to the 5-yard line before the scoring threat ended on Phillips’ interception.

Another big play, this time a 95-yard rushing touchdown down the right sideline for Deal, secured DeMatha’s win, and a jubilant celebration followed.

“It means a lot to get over the hump,” Phillips said. “Coach Brooks didn’t sugarcoat that this was a big game for us. Now we’re focused on getting to the ultimate goal of a championship.”

The Stags defeated the Falcons, 21-0, for the first time since 2010, behind a strong defensive showing. (Nick Plum/The Washington Post)