For the second time in 24 hours yesterday the Washington Capitals, learned that one of their players had injured a knee in the World Championships.

"I'm greatly relieved," general manager Max McNab said after learning that Tom Rowe, 20, had not suffered a major injury, as the Caps first heard, but merely was bumped as the United tates was beating Romania, 7-2.

McNab burned up the international telephone wires to Vienna to reach right winger Rowe, the Caps' third choice in the 1976 draft. "It's just a bruise on the knee," reported McNab. "He'll play his next game Sunday."

The Capitals also got verification yesterday that star Guy Cherron's that definitely would not require surknee injury Thursday was a sprain gery.

Three doctors examined Charron yesterday and placed his knee in a cast to restrict movement.

"We don't know exactly how long Guy will be in the cast, probably a week to two weeks," said a Capital official, "but it's not any sort of permanent injury. He'll recuperate just fine. It's just a matter of a little time. It wasn't necessary to zoom him back here on the first plane."

Another Capital, 32-year-old defenseman Bob Paradise, is also playing for the U.S. in the international matches. "We haven't heard anything from him," laughed a Cap spokesman. "Its his birthday today so maybe he'll be spared."

The club stressed yesterday that it had no second thoughts or complaints about having its players risk injury in the World Championships. "It's an honor to be selected to the U.S. or Canadian team," said McNab. "It's top-flight competition and good experience. The best Russian team is there, for example."

While the U.S., with Rowe and Paradise, was rebounding from Thursday's 4-1 loss to Canada with its victory over Romania yesterday, Sweden beat Canada, 4-2, Russia beat Finland, 11-6, and the defending champion Czechs downed West Germany, 9-3.