Early Friday night, members of the National Football League's negotiating team assembled at an undisclosed meeting place in North Andover, Mass., to await the arrival of their counterparts from the players' union.

The secret meeting had been arranged by a Harvard law professor who had told both sides he wanted to attempt to solve the union's strike against the league.

Union representatives never showed up. According to league sources, Jack Donlan, the league's chief negotiator, received a phone call from Ed Garvey, executive director of the NFL Players Association. Garvey said he was upset about apparent news leaks concerning the possible involvement of the professor, Roger Fisher, and told Donlan the union wouldn't accept the Harvard man as a mediator.

The NFLPA maintains, moreover, that it never agreed to a meeting in the first place.

"The management council is the gang that couldn't shoot straight," Garvey said yesterday. "On Thursday, Donlan and I agreed to let Fisher get involved, but Fisher was going to set up the meeting. Gene (Upshaw, NFLPA president) and I waited in my office until 11 p.m. Thursday for a call from Fisher and it never came, so Gene flew to New Orleans the next day. We get a call on Friday from Fisher saying the meeting is all set up. Then we start getting newspaper calls.

"I finally told Jack we didn't want Fisher involved. Fisher called me twice early this morning and said he couldn't hold the league people up there any longer. I told him to release his hostages, that we weren't coming."

The NFLPA backed away from Fisher, sources said, because the union was uncertain both about his connections with the league and about whether he was seeking publicity for his involvement. Fisher could not be reached for comment.

This bizarre episode left Donlan livid and has further strained relations between the union and the management council, which apparently feels it was deceived about the meeting by the union. It has left the stalled negotiations in no man's land, with the NFLPA again yesterday requesting resumption of talks. Under labor law, the NFLPA has the right to ask for a wage scale, but the council has refused to bargain until the union drops that demand.

"When you threaten to end the season if a settlement is not achieved by Oct. 25, you must realize that we have only 14 days to meet your deadline," Garvey and Upshaw told Donlan in a telegram yesterday. "We stand ready for round-the-clock negotiations starting immediately."

The NFLPA was referring to a story in Saturday's editions of The Washington Post in which NFL Commissioner Pete Rozelle said that unless a settlement is reached and players are back in camp by Oct. 25 or 26, the season could be called off.

It was apparent yesterday that pressures are increasing on both sides to begin talking and reach a settlement.

The union was searching for possible private mediators who would be acceptable to management. NFL sources were putting out the same message: before the season is called off, teams will open up camps and invite in striking players. That move, which almost certainly will be taken before the season is scrapped, most likely will come within two weeks, with an announcement possibly being made sometime this week.

Charles Sullivan, chairman of the management council's executive committee, admitted yesterday that the NFL had no idea how many players would come back or how many had to return in order to resume the season. But in an interview with Associated Press, he said the owners definitely were considering opening up the camps or calling off the season.

"You look at the employment figure. Ten percent of the people in this country are out of work. And we are offering $1.6 billion over five years to 1,500 young men to continue to work," Sullivan said.

Meanwhile, seven Tampa Bay players accused members of the team's coaching staff of calling the athletes and asking if they would cross picket lines and if they support the wage scale. Dave Stalls, the Buccaneers' player representative, said that management "is trying to break the union." He said it was another example "of a continuing pattern of unlawful labor practices." Tampa Bay officials had no comment on the accusations.

Brig Owens, who is coordinating the union's all-star games, yesterday cited management pressure on players as the reason he was withholding an announcement of which athletes will be playing in next Sunday's first game in Washington. Tickets priced at $15, $10, $8 and $6 will go on sale Monday at all Ticketron outlets and RFK Stadium.

Owens said no more than eight players had withdrawn from the original two 40-man rosters. A second game will be played Oct. 18 in Los Angeles. The league is expected to seek an injunction this week in federal court to block players from participating.

Senior White House officials also said yesterday that a report indicating President Reagan was planning to get involved in the strike was incorrect. They said he had no plans to intervene.