The National Football League would be required to expand by four teams no later than 1989 and major league baseball would be required to expand by two teams no later than 1987 under proposed amendments to the first franchise-relocation bill reported out of committee on Capitol Hill.

The Senate bill and its amendments, which are sponsored by Sen. Slade Gorton (R-Wash.), also would prohibit professional sports franchises that use municipally owned or operated stadiums from having exclusive contracts with those facilities.

That is a key provision of the proposed legislation because the USFL and the NFL will be competing to use many stadiums when the two-year-old USFL begins head-to-head competition against the NFL in the fall of 1986.

Gorton said passage of the bill would help Washington's effort to acquire a baseball franchise to replace the Senators, who moved to Arlington, Tex., following the 1971 season.

But even Gorton said it is likely that the bill will die without being considered this session. "I can't tell Sen. (Howard) Baker (Senate majority leader) this is one of the bills Congress must debate by the end of the session," he said.

"But it's the first time one (on franchise-relocation issues) has been reported out. We'll be back with a bill very promptly at the start of the next Congress."

Gorton was attorney general for the state of Washington when the Seattle Pilots moved to Milwaukee after the 1969 season. It was through his efforts as attorney general that the American League put expansion teams in Seattle and Toronto.

He said he and his staff had been working on the original bill for about six months when the Colts moved from Baltimore March 29. The bill, S. 2505, was filed the same day.

The bill also establishes guidelines that would permit teams to move to other cities, but would allow local interests the right to match any out-of-town offer for the team.

Under Gorton's proposed amendment, the NFL would be in violation of the Sherman Antitrust Act if it did not expand from 28 to 30 teams by the start of the 1987 season, including the addition of a team in Baltimore, and to 32 by the start of the 1989 season, including the addition of a team in Oakland.

The Colts were moved to Indianapolis, and the Raiders were moved from Oakland to Los Angeles for the 1983 season after winning an antitrust suit against the NFL.

A federal appeals court upheld the decision in the Raiders' case and Joe Browne, an NFL spokeman, said the league will file documents later this month asking the U.S. Supreme Court to hear the case.

"The idea of forced expansion ignores the reality of the pro football scene as it currently exists," Browne said.

"There are already 45 pro football teams in this country, which is more teams than any other professional sport. We face extraordinary uncertainties as to the future of pro football. Some critics say there already is a glut of pro football . . .

"The way you get franchise stability restored and build a foundation for future NFL expansion is by ending the antitrust chaos that currently exists," he said. "We're hopeful that's exactly what the Supreme Court will do after we file our cert petition . . . "

The bill was approved by the Senate Commerce Committee on a 9-to-8 vote, with Sen. Ted Stevens (R-Alaska) casting the tie-breaking vote.

Because of the continuing legal action in the Raiders' case, the NFL was given a three-year grace period in the original version of the bill, but that would be removed under the proposed amendments.

Gorton called the Raiders' antitrust case a "red herring" and predicted it would be settled in the Supreme Court by the time the bill is debated next session.

Gorton filed the amendments the day after the hearings report on the bill was issued.

Gorton said no provisions of his bill would allow the NFL to merge with the USFL or absorb USFL teams. An antitrust exemption was needed in 1966 to allow the merger of the NFL and AFL.

NFL spokesmen have said another merger is impossible with such legislation.