As the Din and Tonics walked onto the basketball court Wednesday, a solemn silence descended upon the Boston Fleet Center.

Anxiously awaiting the Boston Celtics-New York Knicks game, an estimated audience of more than 14,000 rose and listened to the Harvard all-male a cappella group sing the national anthem in its first performance since September.

The Dins' voices resounded in the large hall as they stood on center court, dressed in coats and tails.

On the large TV-screen, pendant above the court, images of the Dins were superimposed on images of the American flag, Boston's skyline and colorful fireworks.

The group was the first ensemble invited to sing at the Fleet Center when it opened in 1995, and last night's performance was the continuation of a long and positive relationship with the Celtics, according to Christopher R. Hart '99, the group's business manager.

"We sing the anthem, watch the game and grab a couple of hot-dogs," Hart said.

David S. Kennedy '99, the group's tour manager, said the event was a great opportunity for the group to sing in front of a large audience.

"It's always an honor to sing the national anthem, especially at an even like this," said Michael J. Kennedy '97-'99, the Dins' president, before leaving the rehearsal room to go on stage.

Paul B. Sun '98, who sings baritone in the group, became an American citizen a couple of weeks ago. He said he was very excited to sing the national anthem in the Fleet Center.

"It's a great way to inaugurate my citizenship," said the formerly Taiwanese citizen.

Though slightly nervous before his first performance with the Dins, Austin B. Brentley '00, who sings bass in the group, left the stage happy.

"I was thrilled by the performance," Austin said before he got into a cab on his way back to Cambridge.

Brentley's sentiments were shared by the rest of the group.

Many members of the crowd said they were pleased with the Dins' performance.

"It was kind of mellow for a sports game," said Virginia Neves, a Malden resident, holding a foaming Budweiser in her left hand. "But they were absolutely fabulous."

Last January, the Dins performed in Salt Lake City, and this past June the Dins sang on the Queen Elisabeth II, a cruise ship traveling between South Hampton, the U.K. and New York.

The Dins will sing at the Harvard Coop's grand opening in the beginning of December and at the Harvard Club in Chicago for the Annual Alumni Awards Banquet in March, before they embark on a world tour next summer