Player representatives from the National Football League's 28 teams gave their union negotiators a strong show of support last night by unanimously approving a resolution reaffirming their present bargaining position while urging owners to suggest an alternative to the controversial wage scale proposal.

Any hope NFL owners may have had that the latest negotiation breakdown on Saturday would weaken the players' resolve to continue the 35-day old strike was dashed by the outcome of the six-hour meeting at union headquarters here.

But the resolution, plus later comments by NFL Players Association leaders at a press conference, made it clear the union was willing to move away from its wage scale demand, as long as any management proposal addressed the five key points that have been the backbone of the NFLPA's bargaining since late August.

"After all these months, management has still refused to come up with any kind of a wage system that addresses the basic problems," Ed Garvey, NFLPA executive director, said. "The wage scale . . . is the only way we know of to address these issues. But what we have said is that we are certainly open to any proposal to solve these problems . . . if they have some."

Gene Upshaw, NFLPA president, said, "It's not an issue of the wage scale. It's an issue of collective bargaining versus individual bargaining . . . We want the five points addressed, that's our position. If they can address those five points with something else, well, we respond to any proposal that is on the table."

The five union demands are: "provide immediate substantial wage increases for virtually all players; guarantee players a fair share of future NFL revenues; eliminate wage inequities; produce longer careers through elimination of incentives to cut older players for financial reasons; and reward performance through significant incentives."

To meet those demands, the NFLPA has been asking for a trust fund that would pay the players on a seniority-based scale with performance incentive bonuses. But the NFL has rejected that proposal, and the league's chief negotiatior, Jack Donlan, says there is no point in resuming talks until the union moves off this demand.

A union spokesman said Garvey was unable to reach Donlan last night to attempt to set up new negotiations. The two are expected to talk today. Donlan will meet today with the executive committee of the management council, although there is no indication whether the NFL will make new proposals.

Yesterday's resolution was proposed by Cincinnati's Mike Fuller, who became involved in a minicontroversy last week when it was revealed the Bengals had written the union urging the NFLPA remain flexible and not be tied unalterably to the wage scale demand.

"The meeting ended in a very positive fashion," Fuller said. "The resolution sums up what this is all about. It urges the owners to come forth with a new proposal. It's not a rejection of the wage scale. Right now, we have no alternative to the wage scale, so why move off it?"

Although the meeting, attended by 100 players, included a number previously critical of union policies, the NFLPA leadership maintained that no one spoke out against any proposals and that no alternatives were offered.

San Francisco's Russ Francis, who last week urged the union to return to work while continuing negotiations, left the meeting early to make plane connections. He said, "For me, individually, it was productive to be there. Everyone here had ideas and many people presented them up there. People were receptive to other ideas."

NFL management had hoped that the Bengal letter and a similar resoultion adopted by 22 Denver players Friday would be read by the union as signs that solidarity was weakening.

Chuck Sullivan, chairman of the management council's executive committee, said on NBC yesterday that "there will be a settlement as soon as the players assert control of their union. We feel most players don't agree with the basic issue (wage scale). I think it's good the players reps are meeting today. Ed Garvey has disseminated a lot of false information."

Garvey: "There is no substitute for a good strike . . . What really helps is that everyone is solid and really willing to continue the battle."

Other developments from the meeting included:

* Mediator Sam Kagel's role in future negotiations appears questionable. Garvey said Kagel was still acceptable to the union. But Kagel may not be acceptable to management following a statement yesterday by Washington's Mark Murphy, who said Kagel told him Saturday that Donlan "was following the marching orders of the owners and did not have any authority" and that Donlan "was a liar" because he misrepresented Kagel's feelings about the union's wage scale demand.

* The union now is confident, according to Garvey, that any attempt by the league to open up camps would fail. "If they open up camps, no one will come in," Upshaw said. "That's what was so important about this meeting. Everyone was brought up to date and people found out that everyone thinks alike. We have unity and that's not going to break down."

* The strike will not end until there is a new contract, Garvey said. "We are a long way out there," Garvey said. "We could not in good conscience go back to work without a good contract."

* Garvey reiterated that the union wants a "reopener clause" in any contract that would renew negotiations if the NFL signs a cable television contract during the life of a new collective bargaining agreement.