NFL teams begin training camp with a maximum of 90 players. By the start of the season, teams need to trim that group to 53 for the active roster.
Between injuries, players on other teams, free agents and other factors, the shuffling of a roster is a seemingly never-ending process for NFL general managers.
Throughout the season, players can wind up having a variety of different roster designations as teams look to upgrade at certain positions and account for injuries at others.
Take a closer look at NFL roster designations:
IR: Injured reserve
Officially, the term is reserve/injured list, but it's commonly referred to as injured reserve or IR. Players are put on IR when they have a football-related injury that requires them to miss at least a few weeks. Players on IR don't count against the 53-man active roster limit, but their salaries count against the salary cap.
Players on IR must miss a minimum of four games. Teams may designate up to eight players to return from IR during the regular season (and up to 10 if a team makes the postseason). An individual player can be designated twice.
Once a player on IR is cleared to practice, they have 21 days to either be activated to the active roster or be placed on season-ending IR. They can also be released or traded.
Players who are placed on IR before the start of the regular season can miss the entire season, unless they are designated to return when the roster is trimmed to 53 players prior to the start of the season.
PUP: Physically unable to perform
Like players on IR, players are put on the active/physically unable to perform list (or PUP) at the start of training camp because of a football-related injury. The difference is these players count against the active roster limit.
Players on the PUP list can participate in all team activities except practice. They can be activated at any point during camp once they are medically cleared. A player can't be placed on the PUP list after they have practiced or played in a preseason game.
Players on the active/PUP list can be moved to the reserve/PUP list during the preseason roster cutdown period. Players won't count against the active roster limit if they're placed on the reserve/PUP list and they must miss the first four games of the season.
NFI: Non-football injury/illness
Players who suffer injuries outside of football or have a long-term illness are placed on the non-football injury/illness list. Rookies who are still recovering from injuries suffered in college are often placed on the active/NFI list to start the season.
Players who remain on the NFI list after the roster is set at 53 at the end of camp can be placed on the reserve/NFI list and will miss at least four games. They don't count against the 53-man active roster limit.
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