The Soviet Embassy volleyball team defeated the Brazilian Embassy in a hard-fought, best-of-three playoff late Tuesday night to win the Embassy Volleyball League regular season championship. And they did it without any help from members of the Soviet National team.

The rematch between the two teams had been steeped in controversy because, after they lost to the Brazilians last month, the Russians had added the names of two members of their national team to their embassy team roster. They later insisted it was a joke when the Brazilians filed a formal protest.

Nearly 500 people watched the emotional rubber match, which was made necessary earlier in the evening when the Russians defeated the Brazilians 2-1 to end their season in a tie for the title with the South Americans. Both teams had each lost two matches.

That set up a climactic final match in the tiny gym of Georgetown's Duke Ellington School that began with the Russians winning the first game, 15-9, and the Brazilians taking the second, 15-8.

In the third and last game, the Russians edged the Brazilians, 15-13, ending the brutal 3 1/2-hour marathon at 11:30 p.m.

Gennadi Vasilenko, the team captain and Soviet embassy star who played dispite a barely healed sprained ankle, said yesterday that there were no hard feelings.

"We were lucky to beat them," said Vasilenko, who insisted he had inserted the names of the national team members as a prank. "They are a very good, young team. We are all about 40 years old and they are about 25.

"They somehow didn't trust us, but we are friends and we never did anything wrong," he said. "After the game, they apologized to us and we shared beer together."

"They deserved to win," said Brazilian team member Silvio Torres who had filed the protest. "We had one player we had brought to add to our team if the Russians brought their star players. But we never used him, either."

Anna E. Honabach, the D.C. Department of Recreation employe who organizes the league, said she was finally convinced it was, in fact, all a joke.

"It was a marvelous game," she said. "It was the largest crowd we ever had. We even had to add extra seats."