The NFL has asked an arbitrator to dismiss the challenge by the Washington Redskins and Dallas Cowboys to salary cap reductions imposed by the league, according to a person with knowledge of the case.

The league’s request asserts that because the NFL Players Association agreed to the salary cap cuts, the teams should not be able to contest them, according to the person, who provided the information on the condition of anonymity because the arbitration proceedings are confidential.

It’s not clear when the arbitrator, University of Pennsylvania law professor Stephen Burbank, will rule on the request. A hearing in the case is scheduled for May 10.

The league’s effort to have the case dismissed was first reported by the Web site Profootballtalk. The NFL and the Redskins declined to comment on the league’s efforts to have the case dismissed.

The league imposed salary cap cuts on the two teams because of the way they structured players’ contracts in 2010, when pro football had no salary cap. The Redskins’ salary cap was cut by $36 million over two years, and the Cowboys lost $10 million in cap space over two years. Both teams have denied wrongdoing.

Burbank, according to experts, must weigh the league’s interest in maintaining competitive balance against the teams’ contention that they violated no salary cap rules.

Jeff Pash, the NFL’s general counsel, said during a meeting with sports editors Friday in New York that he had “a high degree of confidence” in the strength of the league’s case if it goes to a hearing.

The NFL’s collective bargaining agreement gives Burbank exclusive jurisdiction to enforce certain articles of the labor deal, including those governing the salary cap. It could be difficult for the Redskins and Cowboys to seek relief in court if their grievances are dismissed.

Under the CBA, a decision by Burbank could be appealed to an appeals panel.

According to people familiar with the case, the league found that the Redskins and Cowboys technically violated no salary cap rules but attempted to gain an unfair competitive advantage by reworking some player contracts to pay player salaries in the uncapped year instead of subsequent seasons with salary caps. That allowed the teams to clear salary cap space in capped seasons.

The salary cap reductions were imposed as part of an agreement between the league and the players’ union, and later were endorsed in a vote of NFL teams.

Staff writer Jason Reid in New York contributed to this report.