Students began lining up outside Comcast Center at 6 a.m. on Saturday morning, withstanding a breezy and rainy day to fill the stands once the doors opened three hours before the 6 p.m. tip-off. Sometime around mid-afternoon, Maryland freshman guard Seth Allen and his teammates staged a drop-in, thanking the fans for supporting the team. They tossed a football and posed for pictures, pretending to nap beside one fan who had camped out since Wednesday.

When the Terrapins finally entered the building for their game against No. 2 Duke, they were ready to cash in on the excitement and expectations that had previously seemed to overwhelm them.

Riding the waves of energy revving throughout Comcast Center like a motorcycle engine, the Terrapins sparked their second court-storming in exactly one month with an 83-81 win over the Blue Devils. With its NCAA tournament chances hanging by a thread, Maryland summoned enough magic to, at least for one night, patch the hole in its résumé.

Never before had the Terps (18-7, 6-6 ACC) seemed as energized this season, rejuvenated following a soul-searching six-day break that saw junior guard Pe’Shon Howard suspended for violating team rules, and both Howard and James Padgett stripped of their captaincy by Coach Mark Turgeon. The Terps traded blows with the hated Blue Devils, and when Quinn Cook missed a desperation heave at the buzzer, just seconds after Allen calmly drained two game-winning free throws, the game was finally in Maryland’s grasp.

“I was so hot,” Allen said of the postgame chaos. “Everyone was grabbing me. They picked me up. I just tried to get out of there.”

Sophomore center Alex Len, outmuscled in the teams’ first meeting three weeks earlier, finally brought the fire that has NBA scouts drooling, finishing with 19 points and nine rebounds. The Terps shot 60 percent from the field, attempted a season-high 34 free throws and outrebounded the Blue Devils by 20. Even while coughing up a season-high 26 turnovers, mostly on overzealous dribbling and errant passes, the Terps managed to keep Duke (22-3, 9-3) at bay, entering halftime up 35-34, just their second lead at intermission over the past eight games.

“I challenged Alex about being Mason Plumlee’s little brother,” an emotional Turgeon said of the matchup between the teams’ premier big men. “He treats you like a little brother. I said: ‘I’m tired of being a little brother since I’ve been here. It’s time for us to step up, act like we’re one of the big guys on the block.’ Obviously we’re not. We’re only 6-6 in the league. But we beat a really good team tonight. Is it a breakthrough win? We’ll see.”

Pounding at Plumlee to start the second half, Maryland forced an early timeout after Allen made a three-pointer from the top of the key. As Allen and Dez Wells (nine points, seven rebounds, seven assists) stood at midcourt, flapping their arms and imploring the crowd to up the volume, freshman Shaquille Cleare sank two free throws that gave the Terps an eight-point lead, their largest of the game until Allen did the same less than two minutes later, pushing the margin to 10.

As Maryland’s spoiler show on the national stage stampeded toward the finish, Wells and Plumlee fouled out within 12 seconds of each other. Rasheed Sulaimon, who notched a career-high 25 points in Duke’s 20-point blowout on Jan. 26, hit three free throws to knot the score with 16 seconds left. But the second-half collapse that has befallen Maryland so often in this rivalry never came. And so a matchup nearing extinction, its expiration date coinciding with Maryland’s 2014 move to the Big Ten, served up a masterpiece.

“We talked about pride and passion, playing with those two things tonight,” Turgeon said. “For us, and for our fans. Never quit, never had a doubt we were going to win the game. Just really proud of my kids.”

After a timeout, Allen bided his time before crossing over against Cook and surging into the lane. Cook bumped him along the way, sending the pencil-moustached freshman to the line. With the arena graveyard silent, Duke guard Tyler Thornton began jawing in Allen’s ear. Maryland’s Nick Faust responded in kind, easing the tension and relaxing his teammate. So before Allen sank the biggest free throws of his life, first he began to laugh.