The Washington Capitals do not play again until St. Louis visits Capital Centre on Thursday, which is good news for Bob Carpenter.

Carpenter, who never has missed a game while playing 344 since he entered the NHL in 1981, learned once again Saturday that he is not made of iron, after he was hit in the back of the head late in the first period of the Capitals' 6-2 victory over the New Jersey Devils.

Carpenter had to leave, the third time this season he has been forced out of action during a game. Preliminary X-rays were negative and Carpenter, who rode back on the bus with the team, was examined here yesterday by Dr. Stephen Haas. Afterward, the Capitals' team physician reported that there appeared to be nothing more than a bit of a whiplash effect.

Although Carpenter said yesterday that he felt much better and hoped to practice today, it was one more frustrating incident for the young center, who has only seven goals and 10 assists in 24 games and shares seventh place with Larry Murphy in the Capitals' scoring race.

A year ago, Carpenter set an NHL record of 53 goals by a U.S.-born player and, after signing a four-year contract worth $1.3 million, he was looking forward to a banner year.

However, Carpenter was cross-checked in the back by Philadelphia's Dave Poulin in the opening exhibition Oct. 20 and suffered muscle damage. He aggravated the injury in his only other preseason appearance, against Minnesota 12 days later.

Carpenter still was hurting when the season started and things got worse when he was forced to leave a game in Winnipeg Oct. 25 after being slashed in the hand. He had trouble holding his stick and when the hand was struck again in Pittsburgh Nov. 6, he had to retire once again.

The upcoming break in the schedule affords Carpenter a chance both to heal and to relax.

Despite his physical problems, Carpenter was maintaining a more positive attitude than he did two seasons ago, when he played the first quarter of the season with a bruised shoulder and scored only two goals in 22 games.

"I realize I'm not contributing the way I should, but as long as the team is winning I'm not going to worry about it," Carpenter said. "I'm sure the goals will start to come for me, maybe when they're needed more than they are now."

If Carpenter seemed unable to avoid pain, another Capital with a history of physical problems was rejoicing in a run of good luck and good health. Goaltender Al Jensen, who blocked 34 shots Saturday, extended his unbeaten streak to seven games.

Jensen was voted the starting goalie on the Prince of Wales Conference All-Star team in January 1984, but a back injury ruined the rest of that season and last year he was hobbled by knee problems until surgery repaired what was termed an abnormally tight fibrous band.

"Al is playing the way he was when he was an all-star, before the injuries got to him," said Coach Bryan Murray. "It's so critical to get the quality goaltending he's been giving us.

"If you give up an average goal where the players think you should have handled it, it has a bad effect. On the other hand, if you make a big save, the players seem to bounce right back and put pressure on the other team.

"Al has been making a lot of big saves. Last night he moved out and challenged the shooters, and he stood up well. Any second shots were swept away pretty quickly."

As for past problems with his health, Jensen is reminded of them only by inquiring reporters.

"I don't think about it," Jensen said. "I just put it in the back of my head. I work as hard as I can every time I go out there and -- touch wood -- so far this year things are going pretty well."

Jensen has frustrated the Devils consistently, posting 11 victories and a tie in 12 decisions.

"They always give us a good game and they forecheck well, but the way our team plays such good defense we generally do pretty well against them," Jensen said. "Playing behind a defense like this is a pleasure for any goaltender."

Right wing Ed Kastelic was called up from Binghamton of the American Hockey League yesterday and will skate at today's practice. That puts the Capitals three men over the playing roster of 20 and figures to leave some marginal players mightily concerned, which might be management's intention.