The NFL Players Association has sent a letter to NFL owners urging they bring back the locked-out referees and stressing that failing to do so impacts the safety of the players:

Your decision to lock out officials with more than 1,500 years of collective NFL experience has led to a deterioration of order, safety and integrity. This affirmative decision has not only resulted in poor calls, missed calls and bad game management, but the combination of those deficiencies will only continue to jeopardize player health and safety and the integrity of the game that has taken decades to build.

As we predicted and explained to you weeks ago, the removal of the veteran officials from regular season games left a group of your replacements who have proved to be incapable of keeping pace with the speed of the game.

The letter also criticizes NFL Commissioner Roger Goodell for his public stances on player safety and his willingness to fine players heavily for hits deemed illegal on the field. The letter also notes that the two sides in the referee lockout are reportedly only about $60,000 apart per team in reaching an agreement.

Although the NFL players cannot strike because of rules in their collective bargaining agreement, the CBA does give players the right to refuse work if they believe their safety is in danger.

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This story was originally published on SBNation.com.