POTOMAC, MD - November 9: Georgetown Prep's Carl MacCartee (46) joins the celebration after the Little Hoyas defeat Bullis 21-5 Friday night in Potomac to win the IAC title. (Doug Kapustin/For The Washington Post)

As Georgetown Prep’s Andrew Johnston caught a slant pass, broke a tackle and sprinted toward the end zone, the Little Hoyas’ sideline pleaded loudly. Johnston stumbled briefly but kept his feet, leaving a Bullis defender in his wake. On a rainy Friday night in Potomac where points were at a premium, Johnston’s ability to stay upright and scamper 87 yards for a crucial early score in the Little Hoyas’ 21-5 win helped secure the Interstate Athletic Conference title.

“I was running for my life,” Johnston said. “I was expecting someone to chase me down.”

When no one caught him, the Georgetown Prep sideline erupted.

The Little Hoyas (8-1, 5-0) never looked back, winning the title outright and staying undefeated in the league a year after they shared the title with rival Landon.

“Last year, I thought we had a chip on our shoulders because we had the title but we weren’t really champions,” said Little Hoyas captain Justin Clark, who had an interception. “This was our goal throughout the summer from Day One. Take that ‘co’ out and be outright champions.”

Johnston’s touchdown catch was a crucial momentum swing after Prep fumbled the opening kickoff, giving Bullis the ball on the Georgetown Prep 12-yard line. But the defense stood tall, stopping the Bulldogs with a three-and-out. Bullis missed a field goal try.

“Our first defensive stand was phenomenal,” Georgetown Prep Coach Dan Paro said. “I talked to the boys before the game about embracing adversity because it’s your best friend. They were put in a lot of bad situations, and they just kept fighting.”

More adversity came when Bullis blocked a punt, leading to a safety. But the Little Hoyas’ defense stepped up again. On the ensuing drive after Johnston’s touchdown, the Bulldogs were driving before consecutive sacks by Abdul Jawara and William Tinsley forced a punt. The Bulldogs had minus-12 yards in the first half.

Bullis (7-3, 3-2) tried to regain the momentum to start the second half as running back Eric McKan marched 64 yards on seven rushes, which led to a field goal. But Georgetown Prep’s quarterback Peter Davin connected with Emmet Scanlon on the next drive for a 76-yard touchdown. Davin found wide-open Johnston for another 40-yard touchdown pass later in the third quarter to seal the game.

“They had 10, 11 guys in the box,” Paro said. “At the end of the day, play-action, they’re all coming downhill, and [the receivers] slipped free.”

The victory marked the second straight for Georgetown Prep over Bullis, and the Little Hoyas — and their fans — celebrated afterward by chanting “IAC!” on the field.

“I can’t even put into words. It’s a dream come true,” Clark said. “The defense has carried us, and here we are, champions.”