National Football League players who sued the league for alleged antitrust violations liken the league to a "cartel" in their latest court filing, again urging an appeals court to lift the lockout.

In arguments filed in the 8th U.S. Circuit Court of Appeals, just minutes before Friday's midnight deadline, lawyers for the players reiterated their argument that the NFL has violated antitrust laws, causing the players irreparable harm. They also argued the lockout is illegal and designed to force players to make immense financial concessions.

"The NFL's only interest in preserving the lockout is to use its overwhelming bargaining power to force the players to reunionize," the players' lawyers wrote. "By contrast, the lockout is imposing immediate, career-ending threatening harm on players and may deprive the public of the 2011 professional football season."

The longer the fight over how to divvy up $9 billion US in annual revenue drags on, the closer the league and players get to missing games. The first pre-season game is Aug. 7, with the regular season opener between the Saints and Packers set for Sept. 8 in Green Bay, Wis.

In Friday's filing, the players reiterated that the decision to dissolve their union was their lawful right, and the absence of a collective bargaining agreement shouldn't stop the NFL's ability to "conduct professional football." And, they argued, the harm they would suffer isn't comparable to the league's argument that it would suffer an "intangible blow to their 'negotiating position' and 'leverage."'

"The overwhelming inequity in that imbalance is patently obvious," the players' lawyers wrote.

The players have argued all along that their careers are being harmed by the work stoppage -- they can't work out, or sign contracts with any of the 32 clubs while the lockout persists. A federal judge in Minnesota agreed and lifted the lockout April 25, but the league appealed.

The appeals court reversed U.S. District Judge Susan Richard Nelson's decision just four days later. And on Monday, the appellate court ruled the lockout can stay in place until a full appeal is heard on whether it is legal. That hearing is set for June 3.

Support

The players got some support Friday from other pro players and fans. The unions for hockey, baseball and basketball players filed a legal brief saying the lockout should be lifted because professional athletes' careers are short, and the loss of even part of a season causes personal and professional injuries for which they can't be compensated.

In their filing, the unions for the MLB, NBA and NHL wrote, "there is no off-season in professional sports — only the portion of the work year during which no games are played." The unions said that part of the year brings opportunities — such as the option to change cities, teams or the trajectory of one's career.

Also Friday, a non-profit group that has been fighting sport work stoppages said the lockout should be lifted. The Sports Fans Coalition, which says it gives fans a voice on public policy issues and fights for fan access to games, said in a legal brief that the lockout is not in the best interest of fans, who pay billions of dollars to see their teams perform.

The group of players suing the league, including star quarterbacks Tom Brady, Peyton Manning and Drew Brees, have said the lockout is inflicting irreparable harm on their brief playing careers by preventing them from working out at team headquarters, holding full practices with teammates and coaches and jeopardizing games.

The NFL has argued in its appeal that lifting the labour lockout without a new contract in place would allow better-off teams to sign the best players, tipping the NFL's competitive balance and damaging the league.

The league also said that lifting the lockout with no labour deal in place would cause chaos, with teams trying to make decisions on signing free agents and making trades under a set of rules that could change drastically under a new agreement.

The league says the union's move to decertify after the initial bargaining talks broke down is a sham; that Nelson does not have the jurisdiction to lift the lockout; and, that she should have waited for a decision from the National Labor Relations Board before issuing that ruling.

The players also have a federal antitrust lawsuit against the league pending before Nelson. And lawyers for the players filed documents in U.S. District Court on Friday, opposing a league request for more time to respond to the claim. The league has argued it shouldn't have to respond to the lawsuit until the appeal over the lockout is resolved.

But the players say the lawsuit will go forward whether or not the lockout is lifted and that the NFL's request for an extension is "yet another deliberate step in their campaign to crush the players by extending the lockout for as long as they can."