It appears the NFLPA is preparing for a legal battle with the NFL over its new anthem policy.

The NFLPA has hired multiple law firms to begin researching potential avenues to fight the league's policy, a source told Pro Football Talk's Mike Florio.

Florio suggests the players' association could challenge in the form of a non-injury grievance under the collective bargaining agreement. In this case, the argument would center around the league's failure to engage in good-faith bargaining with the union before altering the policy and removing a right it had previously given to players. The deadline for filing such a grievance would come in late July.