A betting man who watched the Pittsburgh Penguins shackle the Washington Capitals in Pittsburgh Sunday probably would have no hesitation about backing the Penguins in tonight's 7:30 rematch at Capital Centre. He would be reckoning, however, without Washington Coach Gary Green.

It is a tribute to Green's skill behind the bench that the Capitals have climbed into playoff contention with a 16-4-3 record on home ice since Dec. 15. It is a commentary on the club's lack of depth and sorry physical state that the road mark in the same period has been 5-15-4.

Crowd noise, familiarity with boards and ice conditions, eating habits away from home and the exigencies of travel have all been cited through the years as reasons for the ability of home teams to record almost two-thirds of hockey victories.

Ninety-five percent of home-ice advantage actually is derived from the rule that gives the home team the right to make the lat substitutions following a stoppage of play. In effect, the home coach can send out any player he wishes against the visiting units.

Green, after scouting the opposition, either in person or on film, determines how his lines can be used most effectively.He has, on occasion, revised his own lines for a particular game to derive maximum advantage from a player-on-player format.

He has also fooled both opponents and speculators with unexpected matchups, for example his utilization of Rolf Edberg's line against Philadelphia's Ken Linseman line on Saturday.

Green can be very stubborn in forcing desirable matchups, changing several times before a faceoff if required to do so. He does not feel it should be necessary and has discussed the situation with Scotty Morrison, the NHL's referee-in-chief.

"All coaches do not try match up, but if they do, it should be a simple matter to notify the referee beforehand," Green said. "Then, after a stoppage, he would just point to the visiting coach to make his change. Whether he does, or not, the referee would then point to the home coach for the same chance. Then the puck would be dropped, without further juggling.

"We used it in Ontario and it worked well. Here, some referees let the coaches change a couple of times before they stop it. I'll keep it up till I get my way, but I don't like the effect on the morals of a player who is sent out, without entering the play, and then pulled off."

On the road, of course, Green tries to obtain whatever edge is possible, but he concedes it is most difficult to achieve an advantageous matchup without the opportunity to utilize a deep, versatile pool of talent.

Scotty Bowman, possibly the brainiest of NHL coaches, has been successful for years in escaping opponents' matchup plans by rotating players from one line to another during a game.

Fatigue, bumps and bruises played a part in yesterday's practice, as only 10 players were on the ice.

Winger Paul Mulvey is expected to play tonight since X-rays of his left foot, struck by a shot in Pittsburgh, proved negative. However, the swelling must subside sufficiently for Mulvey to put on a skate, and that could be a problem.

Conversely, the Capitals at least control their own destiny again, following Detroit's 7-5 loss to the New York Rangers. If Washington wins its last three games, it is assured of a play-off berth.