New Carolina Panthers offensive tackle Russell Okung, a one-time candidate for the NFLPA's presidency, had his complaint with the players' union thrown out by the U.S. National Labor Relations Board on Thursday, per NFL Network's Tom Pelissero.

The 32-year-old left tackle, traded to the Panthers this offseason from the Los Angeles Chargers, has until May 20 to appeal the NLRB's decision.

To wit, Okung filed a grievance with his union to the labor board in early March 2020 — calling the NFLPA's proposed Collective Bargaining Agreement, approved by the player-members that month, a “bad faith” negotiation with the major North American sports league.

According to ESPN's Cameron Wolfe, Okung charged the NFLPA with an unfair labor practice with the NLRB, stepping into what could set up a major labor dispute with the league's longtime union representative with a veteran player.

Per Wolfe in ESPN.com:

“In the filing, Okung is accusing NFLPA executive director DeMaurice Smith of pushing a vote on the new CBA through to the entire group of players despite the objections and vote of the NFLPA executive committee.”

Okung, like Green Bay Packers star quarterback Aaron Rodgers, was a big-time dissenter of the proposed CBA, which narrowly passed during the member's leadership committee by a three-vote margin, ending up in the hands of the players, who then approved of the new CBA. The new union-negotiated contract between the NFL and NFLPA, among other things, added a 17th game to the schedule, a hotly contested issue among both players and fans.

It's unclear whether Okung, a 10-year vet in the league originally selected out of Oklahoma State by the Seattle Seahawks with the sixth overall pick in the 2010 NFL Draft, will file said appeal within the two-week deadline period to further object to his accusation of the NFLPA's “bad faith” negotiation.