NFL players compete all offseason and through training camp to make the active roster of their current team — or perhaps even elsewhere.
But staying there isn't easy. Especially with injuries a constant factor in such a physical sport.
When the regular season begins, each team can have up to 53 players on its active roster. That comes after one cutdown date during the summer from the 90-player rosters with which teams open training camp.
Players could end up having other roster designations as teams try to upgrade positions or compensate for injuries at certain spots.
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But what do they mean — to the players and teams?
Injured reserve
Officially, it's called the reserve/injured list but is commonly referred to simply as IR. Teams place players on this list when they have a football-related injury and will need to miss at least a few weeks. Players on IR don't count against the active roster.
If a player is placed on this list before the regular season begins, he's forced to miss the entire year.
The same used to be the case if a player went on IR during the regular season, but the rules have been tweaked and amended a few times in recent years. Starting last year, players need to miss a minimum of four games. NFL teams can designate up to eight players to return from IR during the season, and an individual player can be so designated twice.
When a player is cleared to practice, it activates a 21-day window during which the player must be activated to the 53-man roster or be placed on season-ending injured reserve at the conclusion of that three-week period. They could also be released or traded.
Physically unable to perform
Players put on the active/physically unable to perform list — or PUP — at the start of training camp have football-related injuries, like those on IR, but count against the active roster.
These players can participate in all team activities other than practice and can be activated at any point during camp when they are medically cleared.
A player can't be placed on the PUP list after he has practiced once or played in a preseason game.
Players on the active/PUP list could be moved to the reserve/PUP list during roster cutdowns. If placed on the reserve/PUP list, a player wouldn't count against the active roster and must sit out the first four games.
Non-football injury
Players who are injured outside of football — perhaps working out on their own in the offseason or doing a recreational activity — or have a long-term illness not associated with playing, are placed on this list.
Rookies still recovering from injuries suffered in college often are placed on the NFI list to start their careers.
If a player remains on NFI after the final roster cutdowns, he'll have to sit out the first four games.
Reserve/suspended
Players who are suspended by the NFL for violating league rules are placed on this list and don't count against the roster limit.
What's the difference between waived and released?
Players with less than four seasons of NFL time accrued are waived — meaning they are subject to waivers and can be claimed by other teams. If they go unclaimed after the 24-hour waiver period, they become a free agent.
A player can accrue a season if they are on a team’s 53-man roster for at least six games.
Players with four or more seasons accrued are considered vested veterans and are not subject to waivers, so they become free agents immediately when they are released. This is the case until the NFL trade deadline in October. After that period, all players regardless of their veteran status are subject to waivers.
Players can also be waived/injured, which means the player can be claimed by another team or revert to his original team's IR list after the claiming period. The team can then decide whether it wants to move forward with the player or release him with an injury settlement.
