BOSTON -- In the good old days, the Boston Celtics signed the players they wanted, then went out and fought NBA wars against the Los Angeles Lakers and Philadelphia 76ers.

Times have changed. These days the Celtics are also fighting the wars overseas.

The rules seemed to have changed.

The Celtics first lost guard Brian Shaw to Il Messaggero Roma, and still are battling over a five-year, $6.2 million contract signed in January.

Then there's the case of Dino Radja, a relatively unknown 6-foot-11 forward from Yugoslavia taken in the second round of the 1989 draft. He was forced under a federal judge's ruling to play last season for his old team, and will play again in Europe after an NBA arbitrator invalidated an attempt to extend Radja's original one-year contract deal under a little-known rule.

"I think that all of sports is becoming global. And, unfortunately for the Celtics, these two particular situations are at the cutting edge," said Celtics Executive Vice President Dave Gavitt.

General Manager Jan Volk, one of the masters of the NBA's salary cap, said the cap may be working against the league in a way. "The NBA has established for itself a measure of fiscal stability through its own self regulation, in other words the salary cap. In some ways that self regulation makes the NBA vulnerable to outside competition, particularly from Europe," he said. "At this juncture it's limited in two ways: because European clubs are limited to two foreign players each and because the number of European clubs that have the where-with-all to compete financially are very limited."

Still, Gavitt sees a problem with the European flag waving: "There's good news and bad news in that. We've got people who have some value. I'm hearing from other teams . . . that they are having trouble signing top draft picks this year. Even if there's no problem, the agents are just waving the European flag."

Jerome Stanley, representing Shaw, has proposed what he terms a progressive approach.

"If they were progressive thinkers, they would say, 'Okay, if Messaggero relinquishes their rights, then he can play for them this season. And if Shaw agrees and they agree, then he can rejoin us for the playoffs.' It would be quick, and neat," Stanley said in a telephone interview from Los Angeles.

"But that's the open market place," Gavitt said. "That's the great thing about America. We became what we are today because we are a free society and all of us can get up in the morning and try to earn the best living we can for our families.

"I don't begrudge players the opportunity to go to Europe. But I thik when they sign an NBA contract they have to respect it. A contract's a contract," he said.

In the case of Radja, Gavitt said it was a matter of too little playing time for a player considered a top star in Europe.

"We definitely believe that Dino is an NBA-type player. But here it was a question of minutes. And we felt it would be better for him to be playing in Europe for a few years and improving than sitting on the pine behind our current players," Gavitt said.

Radja signed a one-year contract with the Celtics for the 1989-90 season. But a federal judge ruled that an existing contract with his Yugoslavian team, Jugoplastika Split, held precedence and was still in effect.

Under a settlement, the Celtics extended Radja's contract to cover the 1990-91 season. Everything seemed in order, and Radja gave every indication that he would be in a Celtics uniform in the fall.

But on July 12 NBA arbitrator Daniel Collins ruled the extension violated the NBA's one-year rule, which states that no contract can be extended in the first year of its duration. But Collins sided with Boston's claims that it still held Radja's NBA rights.

His worldwide rights were released, and Radja worked out his five-year deal in Italy, with a window after two years and three years allowing him to play for the Celtics, Gavitt said.