The Washington Capitals ought to be sued for false advertising, in reference to that widely publicized claim that the "Big Bad Boston Bruins" will be at Capital Centre for a 7:30 engagement tonight.

In size and belligerence, the Bruins cannot hold a candle to the big, bad Calgary Flames, who were extinguished by the Capitals on Thursday night, 4-2.

Among the visiting cubs are 5-foot-5 Bobby Lalonde, smallest player in the NHL; 5-7 Rogie Vachon, a goalie even more diminutive than the Capitals' Mike Palmateer, and 5-8 Stan Jonathan, once considered at least the middleweight champion of the NHL.

Perhaps Jonathan is still in shock from that punch Bengt Gustafsson threw his way last season. Anyway, both Jonathan and his reputation were mauled by the New York Islanders' Clark Gillies, a few days before Detroit's 5-6 Dennis Polonich threw a solid right that broke the jaw of Boston's Ray Bourque.

The Bruins' 316 penalty minutes rank them in the lower half of the league, just one minute of sin time above the Capitals. Prominent among those Bruins with low PIMs are perennial Lady Byng contenders Rick Middleton, Peter McNab and Jean Ratelle, playing again after a seige of back problems.

A couple of weeks ago, one could have called the Bruins "bad" in another context and General Manager Harry Sinden did just that after his club, opening with a 2-9-1 record, played a home-ice tie with Winnipeg.

"We sink," Sinden was quoted. "Here's the worst team in hockey and we can't beat them in our own building. We can't come out and play a decent five or 10 minutes. There's no way I can reconcile myself to watch this club."

Few others cared to watch the Bruins, either, and attendence at that Winnipeg game was announced as 8,089, lowest since pre-Orr days.

Either as a result of Sinden's tirade or in spite of it, the Bruins have rallied to win three straignt games, including a 1-10 thriller over Philadelphia, and come here with a six-game unbeaten streak.

During Sunday's victory over the Flyers, rhythmic chanting returned to Boston Garden as "Let's Go Bs" was heard from all segments of the crowd of 13,314 that seemed to fill every seat, although falling more than 1,000 shy of a sellout.

How the freeloaders got in provided one more conundrum for team president Paul Mooney, who stated last week that he thought the Bruins lacked motivation and received the following public retort from Sinden: "Paul Mooney is not involved in the hockey end of this business. The fans feel the same way. But they're not involved in it, either. We are."

Through all the turmoil, rookie Coach Gerry Cheevers has remained his old cheerful, imperturbable self. The only change noted in Cheevers was in his attire, which consisted of monogrammed blazer and tie after NHL stuffed shirts protested his open-collared attire in a Hockey News color cover.

"I don't know anything yet, not one-tenths of anything," Cheevers said. "I can't say becasue I played the game I know it all. Possibly I have to be more professional. I can't put on a coach's jacket and say I'm a coach. A lot of work goes into it. I worked hard when I played and I'm working harder as a coach."

While casting aspersions on his players. Sinden absolved Cheevers of blame for the story start, which might justifiably have been laid to the presence of a circus in Boston Garden, forcing the Bruins to hit the road for 18 days.

"In his job, nobody should have to suffer this type of indoctrination," Sinden said. "It's unfair and every player knows it."

Cheevers chose to ignore the vote of confidence, saying, "I don't think about those things.I'm just thrilled to be where I am. Confidence is slowly sneaking back and the attitude is changing. wThe team was playing badly and that has a snowball effect. Something crazy has to happen to snap you out of it.

"Maybe the Winnipeg game changed it. That was a slap in the face at the whole team. I'm sure what Harry said bothered them. We have to get down to reality. If we don't play hard, forechecking hockey, we won't go anywhere."

With Bourque missing, Cheevers has been forced to suit up his assistant coach, Gary Doak. The veteran defenseman has played well in limited ice time, but there is little doubt the Bruins wish they still had a guy who will be playing against them tonight. Rick Smith, the newest Capital, spent eight seasons in Boston, seven as a teammate of Cheevers, but was left unprotected in the waiver draft and was grabbed by Detroit.

Smith played an excellent game against Calgary and Coach Gary Green commented. "Rick Smith was solid out there. He stood up well, he took the body and he showed great endurance. We had been concerned about his lasting power, but there was no problem at all. We're glad to have him."