CALGARY, FEB. 21 -- There is more hockey left to be played in the Winter Olympics, but if the Soviet Union continues to perform as it did this afternoon, there is little doubt who will win the gold medal this Sunday.

The Soviets easily defeated Czechoslovakia, 6-1, to advance to the medal round as the only unbeaten and untied team.

The U.S.S.R. will carry four points into the medal round.

The Czechs (3-2) also advance, but will carry no points into the medal competition. Had the United States defeated West Germany last night, Czechoslovakia would have had two carryover points. But, with its 4-1 victory, West Germany became the final Blue Division participant in the medal phase.

The easy victory at the Saddledome was the Soviets' fifth straight of these Games and their 13th consecutive in Olympic competition, dating to their upset loss to the United States in Lake Placid in 1980.

The U.S.S.R. dominated the Czechs, putting 44 shots on goal to 21. It's a chilling thought to the rest of the Olympic hockey teams that had the two Czech goaltenders not made several superb saves, the score could have been much worse.

Igor Larionov and Andrei Lomakin scored the Soviets' first two goals 7:07 into the game. In the second period, Vladimir Krutov scored twice and Viacheslav Bykov added a late goal for a 5-0 lead. Midway through the period, goaltender Jaromir Sindel, who gave up the first four U.S.S.R. goals, was replaced by Dominik Hasek.

Valery Kamensky scored the Soviets' final goal with 13:16 to play. To the delight of the crowd, the Czechs ruined Sergei Mylnikov's shutout when Jiri Lala scored with 7:50 to play in the game.

Krutov added two assists for a total of four points. Larionov, with two assists, and Sergei Makarov, with three, each had three points.

The Soviets clearly have placed themselves back at the top of the international hockey pack after losing the world championships, Canada Cup and their own Izvestia tournament in the past year.

They will play Sweden, Canada and either Finland or Switzerland in the medal round. It is mathematically possible for the Soviets to not win a medal. But they are favored to win their sixth hockey gold medal in the last eight Olympics.