All but two of 26 National Basketball Association referees went on strike yesterday on the final day of the regular season, and their attorney said picket lines will be set up when the playoffs begin this week.

The strike was ordered by Richie Phillips of Philadelphia, the attorney for the National Association of Basketball referees, and forced the league to use minor league officials in eight scheduled games.

"The NBA has refused to negotiate or recognize the association as the collective bargaining agent for the referees," Phillips said. "As a result, the referees who are members of the association have gone out on an unfair labor practices strike against the league." NBA referees Richie Powers and Earl Strom are not members and will continue to work.

The NBA issued a formal statement declaring the strike illegal. "Individual contracts between the NBA and referees cover the entire (regular) season, including today's games," the statement said.

"The question of recognition has already been submitted to the NLRB (National Labor Relations Board) . . . The NBA will not submit to irresponsible demands to bypass the NLRB."

"At this stage, it is very unlikely that the referees will return only on the promise of negotiation," said Phillips. "We want to have a contract before we work. We will no longer work without a contract."

In Washington, referees Jake O'Donnel and Joe Gushue arrived at Capital Centre around noon, then left the building about 45 minutes before game time.

They were replaced by Joe Crawford and Richie Jackson, both officials in the Eastern Basketball League, who worked the nationally televised game without incident.

Both teams learned of the switch shortly before the 1:30 tipoff. Bullet coach Dick Motta told his team not to complain about any calls and was a model of decorum on the bench as was 76er coach Gene Shue.

"It took a lot of guts to go out there on national television," Motta said. "I thought they did well.I commend the league for not buckling under. I've been in that position before myself, but the world goes on without you. Maybe some good will come out of it. Maybe they can find eight or nine good young officials for the future."

Added Shue: "I didn't even notice any difference. Now that's a compliment, isn't it? My mother always told me to be kind on Easter Sunday."

But there were allmanner of nasty words flying elsewhere in the dispute.

Phillips told The Washington Post he spoke with NBA commissioner Lawrence o'Brien at 7 a.m. yesterday.

"We notified him that the referees would not work unless we heard by noon that the league was prepared to sit down and negotiate with us," he said.

"We let them know last Monday that we absolutely would strike the playoffs. The vote was 24-0 . . . We held out hope all week, but they refused to negotiate.

"They forced our people into a position where they could do nothing else."

Phillips also charged that the NBA has told the minor league officials, "If they don't work, they will rip up their applications to work in the NBA in the future."

"We realize these guys (the minor league officials) are in a difficult position. They have close ties with some of our people. I'm sure they're uncomfortable about it."

Simon Gourdine, the NBA's deputy commissioner, denied last night the league had threatened or coerced its substitute officials into working, and also said Phillips never called him, or O'Brien, yesterday.

"That's the most absurd statement I've ever heard," Gourdine said. "The officials have been eager to work, to prove themselves. There has been no coercion on our part. I'm surprised he would make that statement."

Gourdine also said the league "deplored the strike and we intend to hold them responsible for any damages. We are now prepared to negotiate individual playoff fees with the officials, just as we have always done in the past."

Both Crawford and Jackson were whisked off the Capital Center floor by a half-dozen security men and escorted to their locker room after the game. They said they were told not to comment. "I wish I could talk to you, but I can't," said Crawford, the son of former major league baseball umpire Shag Crawford.

"At this stage, it is very unlikely that the referees will return only on the promise of negotiation," said Phillips. "We want to have a contract before we work. We will no longer work without a contract.

The league reportedly is paying each man $300 per game, $40 per day per diem and travel-expenses.

The referees association is seeking improved pay and benefits, including severance pay and arbittration in the case of firings. The association also has filed an unfair labor practice suit against the league, and the NLRB is scheduled to rule on that today.

The NBA has refused to negotiate a new contract until the referees association is certified by the NLRB.

The players, meanwhile, most likely will cross the picket lines and play, although CBS reported yesterday that Portland center Bill Walton may honor the strike.

According to Larry Fleisher, counsel for the NBA Players Association, "the players have a no-strike clause in their contract (with the league). With-holding services to honor picket lines amounts to the same thing, I would think."

"I talked to Larry earlier in the week," said 76er forward Steve Mix, his team's player representative. "If we go on strike with them, they could throw an injunction at us and make us play. We hope they get everything they want, but I'm sure we'll play."

Washington and Philadelphia players were generois in their praise of the two substitute officials. Crawford and Jackson were in complete control yesterday in a run-and-gun game and called a total of 50 fouls.

"The league must think they're good ones," O'Donnell said before he left the building. "If they were that good, why didn't they hire them in the first place?"

Shue said he still wanted the real thing.

"I want the best referees, whoever they are," he said. "The (officiating) staff, contrary to what other people will tell you, had an outstanding year overall. Refereeing has never been better. I hope we'll see that in the playoffs.

"It was an easy game for them to referee," added the Bullets' Wes Unseld. "But the playoffs are different."