In the most serious situation of his basketball career, Seth Allen stood at foul line with 2.8 seconds left laughing.

It was the Maryland Terrapins' most important game, and their NCAA tournament hopes were riding on the outcome. But Allen embraced the pressure, enjoying the discouraging words of Duke guard Tyler Thornton and an inside joke told him by teammate Nick Faust.

So with the smile still on his face, Allen took the ball from the referee and calmly drilled two free throws. Moments later, when sophomore Quinn Cook's 35-footer caromed off the rim at the buzzer, it touched off the most raucous court storming ever at Comcast Center, a righteous celebration of Maryland's biggest win in coach Mark Turgeon's two seasons, 83-81, before a sellout crowd of 17,950.

After falling to bitter rival Duke in 12 of the last 13 meetings, losing in humbling fashion to Virginia six days earlier, and failing to register an impressive resume-building victory this year, Maryland (18-7, 6-6) needed this one desperately.

Feeling the pressure most profoundly was Turgeon, who grew emotional when recalling a difficult week following Sunday's 80-69 loss to Virginia.

"I take a lot of pride in my coaching," Turgeon said. "But I haven't done a very good job. It's been a hard week on my family. It was hard on my son last weekend leaving the gym. The fans were so hard on his dad. This is for them."

There were lots of other Terrapins who needed it. After shrinking in a 20-point loss at Durham three weeks earlier, Terps sophomore Alex Len (19 points, nine rebounds, three blocks) thoroughly out-played Duke star Mason Plumlee (four points, three rebounds), who fouled out after scoring half of his previous season low.

Allen (16 points, two steals) needed it as well, after taking control of the point guard duties following the suspension of junior Pe'Shon Howard. Allen had his stumbles on Saturday, committing eight of the Terps' season-high 26 turnovers, including one when he ran right out of his shoe.

But in the critical closing minutes, Allen boldly took control of the Maryland offense. His driving basket with 2:01 left put the Terps up 80-72. But that wasn't enough. Three free throws with 17 seconds left by Duke freshman Rasheed Sulaimon tied the game and required Allen to make one more play. Driving down the right side of the lane, Allen drew the foul that set up his game-winning free throws.

"Kid grew up tonight," Turgeon said.

Allen was prepared for his moment at the free throw line. Turgeon had all the Terps shoot 500 free throws this week. Before Saturday's morning shoot-around, Allen decided to take an extra 100, 50 to each basket, making a total of 85. Thus his comfortable smile when the heat was on.

"I don't even remember what [was said]," Allen said. "I just remember it was funny."

Maryland hopes it's the start of an NCAA tournament push. Four of the Terps' final six games are on the road including Tuesday night at Boston College (11-14, 3-9). Beating Duke in a close game is a major step in the maturation of Maryland.

"I think it means a lot," Allen said. "Just to beat a team of that caliber, it shows everybody how good we are and how good we can be. And we had 26 turnovers and beat them."

Getting most of its points from the perimeter, Duke (22-3, 9-3) grabbed a five-point lead in the first half and threatened to take command behind senior Seth Curry (25 points), who hit 11 of 17 shots, and Cook (18 points, six assists, four steals). But Maryland countered with a huge edge inside, out-rebounding Duke 40-20. In a combined 44 minutes, Maryland got 21 points and 10 rebounds from senior James Padgett and freshmen Shaquille Cleare and Charles Mitchell.

After failing to score in the first half, Sulaimon (16 points) heated up after intermission, keeping Duke close. With less than seven minutes left, Maryland turned a one-point lead into a 10-point edge as Dez Wells (nine points, seven rebounds, seven assists) scored on a breakaway slam and hit two free throws. Allen and Padgett added four points each as the Terps had a 77-67 lead with 3:39 left, before Duke rallied.

But in the end, Maryland had too much Allen as the Terps dealt Duke coach Mike Krzyzewski a tough defeat in perhaps his final visit to Comcast Center as Maryland joins the Big Ten in 2014.

"We don't look at any rivalries. We look at playing every conference opponent the same," Krzyzewski said. "If it was such a rivalry they would still be in the ACC. Obviously they don't think it's that important, or they wouldn't be in the Big Ten. We have great games against a lot of people. A lot of people want to beat us, and they're one of them."