It will be an auspicious night of firsts when the Washington Bullets meet the New York Knicks at 8:30 tonight. Not only will it be the opening NBA preseason game for both teams, but it also will be the inaugural event for the Patriot Center on the campus of George Mason University in Fairfax.

The new building won't be responsible for the sellout crowd, though. That honor belongs to Patrick Ewing, the former Georgetown center who will make his professional debut.

"That really makes it exciting for me," said Bullets Coach Gene Shue. "It's exciting that he's playing in the league, and it's exciting that it's us that he's playing against in his first game. I'm sure the players are excited about playing against him."

After a week of two-a-day practices at Fort Meade, the Bullets probably are eager for the change of venue. A scrimmage in yesterday's second session started strongly, but the spirit seemed to fade quickly, the grind starting to take its toll.

"It'll just be nice to play against someone other than ourselves," said guard Jeff Malone. "We're playing the Knicks and Ewing's on their team. That's nice, but it's not like we're scared of him or anything."

Besides, many of the 18 players tonight will have their own concerns in the game. Malone would like to continue to play as well as he did during the final months of last season and rookies such as Steve Black and Tony Costner are hoping to perform well enough to catch Shue's eye.

Forward Kenny Green, the Bullets' first-round draft choice, is playing down the occasion. "I'm not saying I'm not nervous, but you have to stay calm," he said. "I don't have any expectations. I never try to predict what might happen. I think it'll be all right, though."

Shue is planning on a starting lineup of Cliff Robinson and Dan Roundfield at forward, Jeff Ruland at center, and Malone and Gus Williams at guard. After that, Shue said, "We might throw another five in or maybe keep certain guys in against some of their players to see how they match up."

A fascinating possibility is Ewing against Manute Bol, Washington's second-round draft choice. Shue said he was certain that he would make that pairing happen. At first glance, that prospect seems a bit frightening, the powerful 7-foot, 240-pound Ewing against the 7-7 Bol, toothpick-thin at a little more than 200 pounds. But Bol constantly manages to surprise.

Yesterday, for instance, he stuffed a slam dunk attempt by 6-11, 275-pound Ruland, an effort that drew an ovation from the crowd at Fort Meade.

Of Ewing, the Knicks' Rory Sparrow said, "He's shown that he's just a great athlete. "He's already done things that I haven't seen in my years here."

The most impressive may be getting Knicks Coach Hubie Brown to relax. Notoriously intense, Brown now hurls invectives at his players only in every other sentence. During the first days of the Knicks' camp, it wasn't necessary for Brown to raise his voice to Ewing, but Brown said he did not coddle him.

"No matter how good someone is, in whatever, they don't come in and tell us what to do," Brown said. "In business, I don't care if someone went to Harvard Business School. That might get you in the door. But after that you take the basic talent of the person and try and mold it to your specifications."