The NFL’s injured reserve rules will be modified for this season, allowing one player per team to be activated from the IR list, and the sport’s trade deadline will be pushed back.

The changes previously were approved by the sport’s franchise owners. But they were subject to ratification by the NFL Players Association. The union’s approval was announced Thursday, while the Redskins and other NFL teams were mulling roster moves for the start of the season. Each team must reduce its roster to 53 players by 9 p.m. Friday.

“Language being finalized, but there is an agreement between NFL [and] NFLPA on changes to IR and trade deadline,” George Atallah, the union’s assistant executive director of external affairs, tweeted.

Previously, any player placed on the IR list was ineligible to play again for the same team that season. Now each team can activate one player per season from the IR list.

The trade deadline is to come after the eighth week of the season instead of after the season’s sixth weekend of games.

Owners ratified the IR and trade deadline changes in May. The union’s approval was held up, with union officials saying the league also was seeking an increase in the number of practices per season that a team could have with players in full pads. The union was resisting that. It was not clear if any concessions were made.

A person familiar with the changes said the two sides also agreed that beginning next summer, a player who signs with a team after training camp begins doesn’t have to wait until the third day after his signing to begin practicing in pads. Such a player can begin practicing in pads immediately after passing his physical. This summer, players had to wait three days to begin practicing under a provision in the collective bargaining agreement. Redskins offensive tackle Jordan Black was among the players affected.

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