When center Wes Unseld went down with an injured knee nine games ago, Coach Gene Shue's basketball life flashed before him. Unseld was his most valuable player, according to Shue, the hub of the defense and the steadying force of the troubled offesnse.

To compound matters, Unseld's backup, Rick Mahorn, had broken his hand, and the Bullets had only forwards Elvin Hayes and Mitch Kupchak to play center.

The first time the makeshift front court of Hayes at center and Anthony Roberts and Greg Ballard at forwards played together, Washington was bombed in San Antonio by 31 points.

That was 11 days and five games ago and it was also the last time the Bullets have lost.

How can a team with no true center and apparently going nowhere turn things around so quickly?

Simple. Allow the remaining players to play their game and make it as easy as possible for them to do so.

Shue didn't expect Hayes or Kupchak to do the things Unseld did, so the Bullets have gone to a style of offense that doesn't rely that much on set plays.

They run the fast break whenever possible. When they can't, they run what they call a secondary break from a one-four offensive setup. Kevin Porter controls the ball and the other players try to get open.

The purpose of the delayed break and the one-four offense is to utilize the improvisational skills of the players and enable them to maneuver unrestricted by the confines of a set offense. Hayes, Ballard, Kevin Grevey, Kupchak and Porter have run wild with it.

Newcomer Don Collins fits into that offense because he likes to run and create. The man he was traded for, Wes Matthews, didn't, because he had trouble holding onto the ball.

When a team plays such an offense, the point guard handles the ball much of the time and he can't be careless with it.

Not that the Bullets have junked all their plays; they still run them, but not as much.

The big test will come tonight when the Bullets host the Philadelphia 76ers, the team with the best record in the NBA, at Capital Centre at 8 o'clock.

Few teams can run with the 76ers, but the Bullets, with confidence in their new, wide-open attack, will try.

"Our secondary break has really been great," said Porter. "It's opened up a whole lot of things and the players like it because it lets them just play basketball and react to situations. It's not a helter-skelter thing. It's under control, but it gives people a lot of freedom. It's been effective, so we've stayed with it."

Over the last five games, Porter has averaged 19 points and 13.6 assists a game, shooting 57 percent from the field. He has also cut his turnover rate almost in half.

He had been averaging one turnover every 8 1/2 minutres of play, but during this wining streak he has only turned the ball over once every 15 minutes.

When Porter plays well, so do his teammates. For example, Ballard averaged 12.5 points a game before the streak, 18.2 during it; Hayes was in foul trouble and had a sore leg and played only 20 minutes in one game, but averaged 25.3 in the other four, compared with 18.9 before the winning streak; Kupchak was a 10.6 scorer, but improved to 17 a game, and Kevin Grevey has averaged 21.8 the last five games, 16.3 before.

Grevgey had a season-high 30 points in Tuesday's 121-113 victory over Utah. That was olny the second time this season a bullet has scored 30 or more in a game. (Hayes had 34 against Atlanta Nov. 15). Collins made an impressive debut with 10 points, despite, battling the flu. He played exclusively at small forward, but can be used at big guard

He said the Bullet offense is definitely to his liking.

"They have the rebounders and theyh get the ball out and go," he said. "And I can run all day, I like an open game because I'm a one-on-one type player and you need room to do that.

"I think they acquired me to help them with their scoring, so Im not going to come in and be the big scorer.

"He showed in the little time he played against Utah, that he's going to be a great player," Porter said of Collins. "He's fast and deceptive and he's under control.He's a legitmate 6-6 to."

Mahorn, who was put on the injured list Jan. 8, worked out yesterday with his broken hand heavily taped. He is expected to be able to play late this week or early next week. . . Unseld didn't work out.