A federal agency and federal courts will decide the legality of baseball's salary cap.

Players on Tuesday began their attempt to overturn the cap, filing an unfair labor practice charge against owners with the National Labor Relations Board.Players claim owners began negotiations with the intention of forcing a cap. Owners, 0-2 at the NLRB this month, filed a charge against the union, claiming players refused to bargain over wages.

"We'll talk to the parties about the need for relief and begin the investigative process immediately, which means within a day or two," said Daniel Silverman, the NLRB's New York regional director. "Most cases are investigated within four to six weeks. We'll try to stick to that timetable."

If Silverman finds merit to either charge, he would ask Fred Feinstein, the NLRB's general counsel in Washington, to issue a complaint, which is tantamount to an indictment.

If the agency issues a complaint against owners, Feinstein could ask the five-member NLRB for permission to seek a preliminary injunction against the cap in federal court, most probably in Manhattan. That could lead to a court hearing over the cap in February or March.

If a judge issues an injunction, the pre-cap system would return, including salary arbitration, until the case is decided, which could be anytime between 1996 and 1999, depending on appeals.

"If we conclude there is reasonable cause to believe that there is a violation, we would set the matter for hearing before an administrative law judge," said Silverman, who unsuccessfully sought an injunction against baseball owners in 1981. "In those few cases where the delay of the administrative process causes irreparable damage, the general counsel can recommend that we seek a preliminary injunction. Those are two separate decisions."

Silverman said he assigned Ian Penny and Ruth Weinreb to investigate the case. They will interview the lawyers on both sides and examine the paperwork submitted by players and owners.

"From the beginning," union head Donald Fehr said, "the clubs have had one and only one thought in mind: forcing a salary cap upon the players. As the investigation proceeds, we are confident the board will come to see that the clubs entered into negotiations with no intention of reaching an agreement other than upon the clubs' preconceived terms."

The players may have the support of the AFL-CIO, the nation's largest labor organization. ESPN said Tuesday night the AFL-CIO will honor any player picket lines next spring.

Owners implemented the cap Friday after breaking off negotiations the previous night and declaring an impasse in bargaining, their right under federal labor law.

The Major League Baseball Players Association contends there wasn't a genuine impasse and that owners bargained in bad faith, which if proven true would be a violation of the National Labor Relations Act.

The union is reviewing the rules owners implemented and will decide whether to recommend if players should sign contracts until there is a legal determination on the cap.