Three years ago, the Army-Navy Academy boys basketball team suffered through a 3-21 season. The private school hired Terry Ryan as coach, and on Friday night inside the Mira Mesa High School gym, the Warriors capped off a remarkable turnaround.

Anchored by a suffocating defense, No. 1-seeded Army-Navy handed sixth-seeded Ramona a 53-37 defeat to win the CIF San Diego Section Division 3 title.

It’s Army-Navy’s first section championship since 2013.

“This has been a great journey,” said Ryan amidst an on-court celebration. “I love the purpose of this school, trying to raise virtuous young men.”

Army-Navy improved to 23-9 while Ramona fell to 23-10. Both teams advance to the Southern California Regionals, with pairings for the state playoffs will be announced Sunday.

For 10 minutes, it looked like the Warriors would run away from the Bulldogs. Early in the second quarter, Army-Navy’s lead was 23-6. But Ramona went on a 14-4 run, closing the deficit to 27-20.

“Runs happen every game,” Ryan said. “It doesn’t faze us much. We take what we need to do and stay the course.”

And what did the Warriors need to do?

“Take care of the ball and make our layups,” he said.

And continue the stingy defense. A 16-7 third quarter left the No. 1 seed with an 18-point lead. Ramona would never slice the deficit to single digits.

Ivan Marchenko, a 6-foot-7, 215-pound forward from Ukraine, muscled inside for a game-high 21 points. He also grabbed 11 rebounds.

“They elected to play him 1-on-1, and that’s always a mistake,” said Ryan.

Sophomore Ernest Donkoh, a 6-8 wing, scored 13 points and had nine rebounds for Army-Navy.

Donkoh collapsed to the floor late in the first half with a twisted ankle and had to be helped off the court. Apparently he’s a quick healer. He started the third quarter and scored eight points in the second half.

“I had to come back and support my team,” said Donkoh. “I have to kill myself for this team. This is when they needed me the most.”

Taden Bryant, a junior, led Ramona with 20 points, including four 3s.

But Army-Navy’s defense proved too stifling.

Ramona was 7-of-24 in the paint, 6-of-27 outside and 13 of 51 overall (25 percent).

“Our defense was phenomenal,” Ryan said. “In my opinion, we’ve had the best defense in San Diego all year long, and it didn’t disappoint tonight.”