MONTREAL, SEPT. 9 -- Just as the Canada Cup final was shaping up as the Communist Cup, the host team saved the show.

Two goals behind at midgame, Canada scored three times in 2 minutes 25 seconds and went on to defeat Czechoslovakia, 5-3, tonight in a surprisingly tense semifinal.

Mario Lemieux scored twice for Canada, which moved on to face the Soviet Union in the best-of-three final that everyone except the Czechs and Swedes has been eagerly awaiting. The opener is scheduled here on Friday.

Canada, already hobbled by injuries, lost two more players tonight. Right wing Claude Lemieux went out with a sprained left ankle and defenseman Normand Rochefort bruised his right knee.

One of the skating wounded, Dale Hawerchuk, forgot about his bruised right shoulder and scored the goal that woke up the Canadians, the crowd of 10,262 and, no doubt, a worried throng of television watchers from coast to coast.

Czechoslovakia had taken a 2-0 first-period lead on goals by Dusan Pasek and Jaroslav Benak. Then in the second period the Czechs came close again, but goalie Grant Fuhr made an excellent kick save on Vladimir Ruzicka.

With the crowd roaring, Hawerchuk took a pass from Washington's Larry Murphy, skated to the top of the right-wing circle and sent a spinning shot past the glove of Dominik Hasek at 10:43 of the second period. The goalie, who had recorded 13 first-period saves, was screened by his backpedalling defenseman, Bendrich Scerban.

"We were getting frustrated and we knew we couldn't afford to let them get the next goal," Hawerchuk said. "For that one to go in at that time was pretty big for us. I knew once we got the first one, we'd be on our way. It was just a matter of time."

Not much time, either. Glenn Anderson flipped a backhander 23 seconds later that Hasek muffed and allowed to drop into the net. But referee Mike Noeth had blown his whistle on the initial contact, with the intention of protecting Hasek from late hits by the pressing Canadians, so the goal was disallowed.

It hardly mattered, as it took Mario Lemieux only 19 more seconds to tie it officially. A beautiful backhand pass by Michel Goulet freed Lemieux on the left wing and he sailed in to fire the puck past Hasek's glove.

A cross-checking penalty to Ladislav Lubina, which put Claude Lemieux out of the game, set up Mario Lemieux's go-ahead score. Ray Bourque skated down the left wing and put the puck on the stick of Mario Lemieux breaking for the net. He deflected it off the right post behind Hasek at 13:08 and Canada was ahead to stay.

"The goaltender stoned us early, but we knew if we kept getting opportunities, he couldn't stop everything," Murphy said. "We knew if we stepped up the play, we'd get back in the game. Everybody had faith. It just took us a little longer than we really wanted."

After Goulet converted a Wayne Gretzky pass to make it 4-2 in the third period, the Canadians got carried away a bit, trying to pad the score. As a result, they were caught by a two-on-nobody break on which David Volek converted Jiri Hrinda's pass.

Brian Propp squelched any revived Czech hopes by netting a rebound of a Mario Lemieux shot to complete the scoring.

"We were a little flat at the start and they moved the puck around very well," Propp said. "But once we started dumping the puck in and checking their defensemen, we wore their defensemen down and they couldn't get up in the play. They're always looking for the late man and, when he isn't there, it takes a lot away from their offense."

Canada not only pounded the Czech defensemen, it did a pretty efficient job of roughing up Hasek, too. The low point of that tactic came when Claude Lemieux, skating from the rear boards behind the play, punched Hasek in the face.

The goalie took an exaggerated dive, the trainer rushed out with smelling salts and the crowd booed. It was hard to figure whether the fans were unhappy with Hasek's acting or the sorry act of Lemieux, who plays for the Canadiens.