The Washington Redskins placed left tackle Trent Williams on the NFL’s reserve non-football injury list Thursday, eliminating any chance the seven-time Pro Bowl selection will play for them this season.

League rules allow teams to decide whether they want to pay players on the non-football injury list. Considering Williams held out for five months before returning to the team last week and has essentially vowed to never play for Washington again, the Redskins could select not to pay him, keeping him from collecting any of his $10.8 million base salary for 2019.

The Redskins did not immediately respond to a request for comment.

Williams should still get credit for this season toward fulfilling his contractual obligation to the Redskins. That's an important consideration because the primary reason he came back right before the Oct. 29 trade deadline was to ensure this year would be counted under his contract. It means he will have one year left under the deal after this season, allowing him to become an unrestricted free agent after the 2020 season.

According to a person with knowledge of the situation, the Redskins will let the NFL decide whether this season should be counted under Williams’s contract. The Redskins conceivably could attempt to toll Williams’s contract and have it cover the 2020 and 2021 seasons instead of this season and next season. Williams and the NFL Players Association could challenge such an attempt.

The NFLPA declined to comment Thursday. According to a person familiar with the situation, the union will decide later whether to challenge Williams being placed on the non-injured reserve list..

Williams has held out since the spring, refusing to take part in team workouts, practices, camps and games because he says he is angry about the way Redskins doctors handled the diagnosis of a growth on the top of his head. When he returned to the team, Williams alleged the doctors did not take the growth seriously for six years until finally referring him to specialists last winter. The growth turned out to be a rare cancer called Dermatofibrosarcoma Protuberans. While DFSP has a 98 percent cure rate, the experience rattled Williams.

The contentiousness between Williams and the Redskins increased this past weekend when Williams instructed the players’ union not to participate in a joint review with the league of his medical treatment by the team. The NFL previously had said there would be such a review, in which a panel of three medical experts would have reviewed Williams’s medical records and would have made a report to the league and union.

The Redskins could have been subject to possible disciplinary action by the NFL, likely a fine, if they had been found to have mishandled the case. But Williams had to approve the release of his medical records and balked at doing so.

The NFL had given the Redskins a two-week roster exemption for Williams, theoretically allowing him time to get into shape to play games. But Williams did not pass a physical Oct. 30, when he complained of soreness while placing two different helmets on his head. He later said he had three surgeries on his scalp.

Though the Redskins chose not to deal Williams before the trade deadline, they can do so officially before the start of free agency, perhaps getting more in return than they would have if they had traded him this fall.

Kareem Copeland contributed to this report.

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