The NFL announced on Monday that it is filing a grievance against the NFLPA, claiming that the union advised players to feign injury to gain leverage in contract negotiations.

The league announced the grievance in a memo that was reported by NFL Network’s Tom Pelissero. The memo names NFLPA president and former Cleveland Browns center JC Tretter.

“Beginning this past summer and continuing through training camp, NFL Players Association leadership, including President JC Tretter, have become increasingly vocal in advising NFL players dissatisfied with their current contracts to consider feigning or exaggerating injuries to withhold service as a way to increase their leverage in contract negotiations,” the memo reads.

Running back negotiations became contentious this offseason as All-Pros Saquon Barkley, Josh Jacobs and Jonathan Taylor failed to secure long-term contracts. Barkley and Jacobs eventually signed one-year deals while Taylor remains sidelined on the physically unable to perform (PUP) list on the final year of his rookie contract.

PHILADELPHIA, PA – NOVEMBER 01: A detailed view of the NFL logo shield on the goalpost during the game between the Dallas Cowboys and Philadelphia Eagles at Lincoln Financial Field on November 1, 2020 in Philadelphia, Pennsylvania. (Photo by Mitchell Leff/Getty Images)

Other high-profile running backs including Christian McCaffrey and Derrick Henry spoke out in support of their fellow players and reportedly joined a Zoom meeting to discuss how to improve the state of running back pay. Colts owners Jim Irsay criticized the running back complaints and meetings as in “bad faith” at the behest of their agents.

The NFL’s memo referred to that running back meeting.

“We have become aware of a formal Zoom hosted by the NFLPA with certain NFL running backs in which this advice was conveyed,” the memo continues. “This conduct is a clear violation of the union’s agreement to use ‘best efforts to faithfully carry out the terms and…