The Washington Capitals' tenuous pursuit of a playoff berth boiled over into intramural warfare yesterday, as rookies Bobby Carpenter and Torrie Robertson engaged in a prolonged exchange of punches during a scrimmage at Fort Dupont.

Carpenter's jersey was pulled off in the melee, which was broken up by other players and Assistant Coach Yvon Labre. The battle apparently had its roots a few moments earlier, when Robertson's elbow took off Carpenter's helmet in a corner. Then, when the two collided along the boards, they started swinging.

Both players were reluctant to talk about it afterward and insisted that it was no matter for concern, although it was the first outbreak of such intensity at practice this season.

"It's forgotten," Robertson said. "When I was in juniors, we had a fight a practice. It doesn't mean anything. Everybody's close on this team."

"It shows the guys came to the building to play, to impress," said Coach Bryan Murray. "I don't encourage it and I certainly don't want to see anyone hurt, but it shows an involvement."

Carpenter, who was tested often by opponents early in the season, has been involved in only one fight in 1982. He was still sporting a black eye yesterday from that one, a furious battle on Wednesday with Jim Nill of St. Louis, the same night Carpenter scored four goals. Coincidentally, the Blues will be back at Capital Centre tonight at 7:30.

Robertson is a frequent fighter, with 156 minutes in penalties despite limited ice time. He was a standout yesterday, scoring on the first shift of the scrimmage and outskating speedy Mike Gartner for a loose puck.

"I like to play the game hard and I do everything hard," Robertson said. "If you don't play a lot, you have to work extra hard to keep sharp. At 20 years old, I don't expect to play much, but I'm waiting for my chance and, when I'm called to go, I'll be ready. I'm just glad to be here."

"I don't think there's any frustration about not playing more in Torrie's case," Murray said. "He'd rather play a role than go down. He's a chirper, one of the most prepared guys in the dressing room before a game."

Robertson will probably see some ice time tonight alongside center Jim McGeough, who was summoned from Billings because the Western League team is off this week. McGeough, who played briefly in two games with Washington in November, has rolled up 75 goals and 53 assists in 58 games with the Montana juniors.

The Blues come here following a 2-2 tie at home last night against Boston and all indications point to another easy victory for the Capitals. It is those situations that sometimes produce highly unexpected results and Murray has to hope the high pitch of yesterday's practice will carry over.

"St. Louis is going to come here pretty intense," Murray said. "Nobody likes to get rubbed, 9-1. I'm sure there will be some response."

Back at Capital Centre, General Manager Roger Crozier was busy at two tasks. He was trying to persuade Colorado General Manager Billy MacMillan to reduce his price tag on defenseman Rob Ramage, who wants to be traded, and he was preparing his 30-man eligibility list for the playoffs. Hope lingers, despite Pittsburgh's nine-point margin.