Negotiators for the National Football League will present a revised financial package today to the NFL Players Association when the two sides meet under the auspices of a federal mediator for the first time since Aug. 25.

Jack Donlan, executive director of the NFL's Management Council, the league's labor negotiating arm, described the offer, the product of several meetings with team owners over the last several weeks, as a substantial package, but declined to be more specific.

Ed Garvey, the executive director of the players association, said several players have been told by their general managers that the offer will include a 20 or 30 percent pay increase for every player. Donlan denied this was the case.

"We're going to get it tomorrow and take a hard look at it," Garvey said. "We expect them to present their proposal, announce it to the press and then the general managers will try to sell it to the players, but that's not going to work."

Garvey said the players will insist any final settlement include immediate pay increases, guaranteed fair share of future revenues for the players, elimination of wage inequities, elimination of economic incentives for the teams to get rid of older, more expensive players and a system of performance incentive bonuses.

"We think whatever system we have has got to reward performance through significant incentives," Garvey said. "If they're going to hold on to the system of individual negotiations or try to fool around with free agency and right of first refusal, then we've got a long way to go."

The players' basic demand is to be paid on a seniority-based scale, with performance bonuses funded by a trust fund that would collect 55 percent of NFL gross revenues.

The owners say they will never agree to a package based on a percentage of gross revenues. They have indicated they are willing to ease the restrictions on movement of free agents from one team to another, and to reduce the amount of compensation a team signing a free agent must pay the team that loses him.

Today's meeting, at the Crystal City Marriott, was arranged by Kay McMurray, director of the Federal Mediation and Conciliation Service. Through a spokesman, McMurray said, "The parties will make their own presentations, and I will stand by to be of assistance if needed."