The NFL roster rules are both convoluted and constantly changing. For the average fan, the process can be dizzying.

So before we get into the flurry of roster moves for the 2024 Detroit Lions, let’s take a look at four of the most important rules and regulations teams must follow in order to build their 53-man roster before the 4 p.m. ET deadline on Tuesday, Aug. 27.

Waived vs. released

These terms are often used interchangeably, but they are not synonymous. Both refer to the cutting of a player, but only specific players are “waived” vs. “released.” If a player has only accrued three or fewer seasons in the NFL, they are waived. If they’ve been around for at least four seasons, they are released.

But what does each mean?

A player who is waived appropriately goes on waivers, where all teams can put in a roster claim for the player. Of the teams who put in a roster claim for an individual player, the team with the highest waiver priority is awarded the player. If awarded a player, they must go directly to the 53-man roster. You cannot claim a player and immediately stash them on the practice squad. If a player goes unclaimed through waivers, they become an unrestricted free agent free to sign to any team’s 53-man roster or practice squad.

NOTE: At this point in the season, waiver priority is based on last year’s standings, with the worst team (Panthers) having the top priority, and the best team (Chiefs) having the 32nd priority. Currently, the Lions have the 29th priority. After Week 3, waiver priority will be determined by 2024 standings.

A player who is released has their contract immediately canceled and are free to sign with any team they please immediately.

So as it relates to the Lions: if they cut James Houston, he only has three years of experience, so he’ll be subject to waivers. On the other hand, if they cut Donovan Peoples-Jones—who has four years of experience—he will be released and free to sign anywhere.

New IR rule

This year, the NFL is implementing a new rule that was actually proposed by the Lions. In short, a team may place two players on injured reserve on the day of cutdowns (Tuesday), and both of those players will be eligible to return after a minimum of four games.

Previously, if a player were to return in the same season as they were placed on IR, they would have to make the initial 53-man roster and then be placed on IR. This new rule eliminates the need for roster gymnastics.

Coach Dan Campbell has already indicated they have their two players chosen for this new rule: defensive end John Cominsky and cornerback Emmanuel Moseley. At this point, you can probably expect both to be placed on IR on Tuesday.

However, there’s something else to consider here. The Lions have a couple of other players who are also candidates for short-term IR stints. The severity of injuries to defensive tackle Brodric Martin and safety Ifeatu Melifonwu are unknown. If they’re serious enough to warrant time on IR, they likely have to make the initial 53-man roster and then be placed on IR later in the week. Another possibility is that Cominsky or Moseley are placed on traditional IR—thus ending their season—to open a spot for Martin or Melifonwu to take advantage of the new rule.

If the Lions need to do some roster gymnastics, don’t be surprised if they temporarily cut a veteran player (who won’t go on waivers) in order to create a roster spot for these injured players. Then once the injured player is placed on IR, they’ll sign back the veteran.

PUP/NFI rules

First things first: a player who isn’t currently on the physically unable to perform (PUP list or non-football injury (NFI) list is no longer eligible to be placed on the list. That must be done before training camp. And once you’re off the PUP or NFI list, you cannot go back on it. So, in the Lions’ case, DJ Reader is now off the list and cannot be placed back on it.

At the beginning of training camp, some injured players are placed on what’s called the active/PUP or active/NFI. All this essentially means is the player hasn’t passed a physical and is ineligible to practice.

But on roster cutdown day, teams must make a decision on those players. Either activate them from the PUP or NFI—meaning they will count against the 53-man roster—or move them to the reserve/PUP or reserve/NFI. If placed on the reserve list, they will miss a minimum of four games.

For the 2024 Lions, there is only one player eligible for this: rookie guard Christian Mahogany. It seems likely the Lions move him to the reserve/NFI list. If they do, Mahogany will not only miss four games, but he also will not be eligible to practice during that time. He can still work out and attend team meetings, but no field work.

After four weeks, the Lions can clear Mahogany for practice without officially activating him. Once he returns to practice, it starts a 21-day evaluation window. At any point, the Lions can activate him during that window. Once those 21 days expire, Detroit must either activate him to the 53-man roster or keep him on the NFI for the season.

Practice squad rules

Teams can start building their 16-man practice squads starting at Noon ET on Wednesday, Aug. 28 (after all the waiver claims from the initial roster cuts have been processed).

Unlike in the past, every unrestricted free agent is technically eligible to sign on a practice squad. However, there are limitations on the amount of certain types of players you can keep.

• 10 players must have two or fewer accrued seasons
• No more than 6 players are able to have an unlimited amount of accrued seasons
• Teams can keep an extra 17th player on the practice squad if that player is from the International Pathway Program

And don’t forget about “poaching.” Teams are allowed to sign players from another team’s practice squad, but they must join the 53-man roster of their new team. It’s also entirely up to the player if they want to leave the practice squad of one team to join the 53-man roster of another.