It's a dream team that a youngster swapping bubble gum cards might put together.

He'd trade away the fringe players, cut the aging veterans and keep only superstars, one at every position. The result would be an unbeatable combination that could handle even the Boston Celtics at their best.

Unfortunately, bubble gum cards and dreams have had a bad autumn in Houston. That city's NBA Rockets assembled a club with a heavyweight at every spot and a payroll that has to be delivered by a Brink's truck. But all that talent has been battered by one knockout after another so far this season.

Mere mention of the Rockets' main guns make any basketball aficionado sigh: Mike Newlin, Calvin Murphy, Moses Malone, Rick Barry, Rudy Tomjanovich. So what if the bench resembles a 90-pound weakling and a playmaker is nowhere to be found?

The Rocket deficiencies have become so glaring they are chewing away at the dreams, popping the hopes of both rooters and players almost every game.

Houston can't even overtake Atlanta, of all teams, in the Central Division race. Coach Tom Nissalke, according to observers close to the team, could be on the verge of losing his job. The Summit is filled with boos during home games and the players are constantly asked one question: What happened?

The answer, say the Rockets, is simple. NBA Commissioner Lawrence O'Brien ruined their Christmas by ruling that Houston would have to give up John Lucas as compensation for the signing of free agent Barry.

"We never expected to lose Lucas," said Nissalke. "We got Rick with the idea that John would be our playmaker. It stunned us." The Rockets would have preferred giving Golden State as much cash as, say, $500,000 or a draft choice or two.

But hardly anyone else in the league blinked at O'Brien's decision. Golden State had lost one of the league's golden boys and the Warriors needed help that money alone couldn't buy. Lucas, the young and promising guard who eventually might achieve the same star status as Barry, seemed a logical choice.

"The Rockets took a chance and got burned," said one league source. "If Lucas stays, they have a great team. If he goes, they haven't got enough basketballs to keep everyone happy. It was a risky thing to do."

To make matters worse, while Lucas has been sensational in his new home, Barry is playing as if he had left his skills and heart in San Francisco.

Nissalke was on the verge of benching im three weeks ago and only a back injury to Tomjanovich spared Barry that ignominy. He finally put together a stretch of decent games during a recent West Coast trip, but even then was hardly worth $500,000 a year. There are only rare flashes of that once-formed temper and hustle.

Barry has been slowly losing his talent and desire for the last two years. He is content now to take an occasional shot, play inconsistent defense and pretend he's a 6-foot-7 playmaking forward. He'd rather stand at the top of the foul line and pass (he's averaging seven assists) than try to penetrate down the lane, scoring only 16 points a game.

"I'm not making excuses, but for most of the season, I haven't been right, injury-wise," said Barry, who has had a sore back and two sprained ankles, one of which resulted from tripping over a suitcase. "We aren't that far away from being a good team. We just haven't had any consistency. But I'd rather be playing poorly now than later in the schedule."

He'd also rather finish out his career as a nice guy rather than as a villain. So he was worked hard to blend in with his teammates and they, in turn, say he has caused no friction. They don't talk about his seeming indifference on the court.

It is Barry's contention that Houston was robbed by O'Brien's compensation ruling. Few Rocket fans would argue with him right now when he says, "Golden State got the better of the deal. Lucas has got years left, I have two. It wasn't fair to this team. I've been wanting to play with a guard like him for a long time. It's a shame we never had the chance."

Out of desperation Nissalke has tried no fewer than six players, including Barry, at Lucas' playmaker spot. The Barry experiment lasted one game. Slick Watts currently is occupying the position, but that leaves Houston with two small guards defensively in a league where big guards are the latest development.

Although Nissalke would like to make a trade, using Newlin as bait, so far General Manager Ray Patterson, the man responsible for signing Barry, has balked. The Rockets are left with an often-times leaderless offense.

"We aren't quick enough to run," said Nissalke, "So we needed a guy like Lucas to make sure our half-court game worked. He controlled the ball and didn't turn it over. He had poise, just what we had to have."

When all parts of the Rockets' impressive offensive arsenal are meshing, Houston can overcome its defensive problem ("No one is laying awake at night worrying about which Rocket is going to guard them," said Nissalke) and its one-dimensional rebounding ("Malone is going to be dead by midseason it they don't give him some help," said Washington's Elvin Hayes).

Houston's offense comes almost entirely from the outside, save for Malone's relentless assault on the boards. Barry, Tomjanovich and Murphy all would rather launch 15-footers than mix it up underneath.When the longdistance approach works, it can be most impressive. But in the NBA, especially in the playoffs, perimetershooting clubs can be disrupted by stingy defenses.

The one clinging hope in Houston is that it is too early to judge the Rockets. The loss of Lucas, the addition of Barry, the comeback of Tomjanovich are elements that need time to be worked out.

Tomjanovich, for example, is shooting as well as he did before being knocked out by Kermit Washington a year ago. His aggressiveness has been curtailed, although that may change as he gains confidence.

"People forget," said Barry, "that this offense is built around Moses. We look first to get the ball inside to him and then go from there.You are asking a lot of players to learn to play with each other and that takes time. But that is why the NBA season thankfully is so long."

Barry, the part-time TV analyst, realizes that even a winning record won't be enough for Houston fans.

"The only way my signing is going to be considered a success," he said, "is if we make the playoffs. Otherwise, there are going to be a lot of questions about why they wanted me here in the first place."