"What Wayne Gretzky did is the most unheard of thing I've ever heard of."

Minnesota Coach Glen Sonmor, after Gretzky scored five goals against Philadelphia

Five fire engines pulled up outside the Fort Dupont rink yesterday a few moments before the Edmonton Oilers arrived for a practice session. It was most appropriate, because the hottest item in hockey, Wayne Gretzky, is here with the Oilers, who will meet the Washington Capitals for the first time this season tonight at Capital Centre at 7:30.

The firemen were lured by a broken sprinkler system in nearby apartments; Gretzky's specialty is broken records. In 44 games, he has collected 54 goals and 65 assists for 119 points. The NHL marks are 76 goals by Phil Esposito and 109 assists and 164 points, both by Gretzky last season.

One hundred goals and 200 points are not out of Gretzky's range, considering his present rate would bring 98 goals and 118 assists for 216 points. He is scoring an average 2.70 points per game; last season he set the NHL record with a 2.07 rate. This all makes some observers wonder whether he might leave himself no room for improvement. Still 13 days away from his 21st birthday, the absence of further incentive could be the only thing that will stop Gretzky. Certainly, the opposition cannot find an antidote.

"We considered kidnaping him," said St. Louis' irreverent scout, Bob Plager, "but we came to the conclusion that no matter what we might do, there's no stopping Gretzky."

While his teammates boarded the team bus after practice at Fort Dupoint, Gretzky sat in his full equipment on the steps answering questions that he now is asked routinely, to evaluate himself, to compare himself with greats like Bobby Orr.

"I was only 9 or 10 when he (Orr) was in his prime," said Gretzky. "I never thought I could be as good as Bobby Orr... nobody has come close to doing what he did. Nobody can do what he did."

Later, he was asked if 100 goals is a realistic goal for him this season. "I think it's something that can be accomplished," he said. "Three years ago everyone said 200 points, no one can do it. Now I have a chance.Someone will get 200 points, someone will score 100 goals."

Asked how he felt when he got his 50th goal on Dec. 30 against Philadelphia. "Relieved," he said. "I kept imagining at 34 or 35 games, everybody saying, 'He choked.'"

Edmonton owner Peter Pocklington reportedly is considering a new contract that would pay Gretzky $1 million a year. He now is playing under a 21-year personal service contract under which he would get $280,000 in 1982-83.

Washington Coash Bryan Murray is due for a rare treat (or trick) tonight. This will be the first time he has actually seen Gretzky play, although he has pored over videotapes.

"We're just going to have to be very conscious of his wingers and eliminate them as often and as well as we can," Murray said. "... Maybe we'll use a specific line against him. Certainly, we'll have to be a lot more concerned with our defensive game than in the last title while."

Washington defended Gretzky fairly well last year. Ryan Walter shadowed him into a scoreless night in a 2-2 tie at Edmonton and Bengt Gustafsson was the principal checker here as the Capitals blanked him in a 5-2 victory. Gretzky rebounded with two goals and four assists as the teams split their last two meetings. The year before, in his first NHL season, Gretzky tied Billy Taylor's 1947 NHL mark with seven assists in one game against Washington.

"You have to stay close to him, not right up against him but close enough to keep him from passing the puck," Gustafsson said. "As soon as they get possession of the puck, you have to pick him up. It was a good feeling to stop him last year. He's good but he's not all-everything. Maybe you'd better not print that, or he might score 10 goals tomorrow."

Defenseman Paul MacKinnon, who has played against Gretzky as a junior, in the World Hockey Association and in the NHL, said, "He is aware of everything on the ice. Some people have more or less tunnel vision, but he sees the whole surface. It makes my job that much tougher, because if he's coming at me I have to be aware of where his wingers are and try to anticipate as much as he is."

Billy Harris, the Oilers' assistant coach, said, "When you sit in the press box, you see the whole ice surface. Sometimes you see open men and wonder why a player didn't pass to them. Wayne is one of those rare individuals who can see at ice level what you can see up high. He always finds the open man."

Despite his talent and performances, Gretzky lacks the crowd appeal of a Gordie Howe, Bobby Hull or Bobby Orr. Washington trainer Bill Bozak thinks he knows why.

"Half his moves are so slick, the fans don't even notice them," Bozak said.