The NFL's annual judgment day is nearly here.

The Detroit Lions will trim their roster to 53 active players by Tuesday's 4 p.m. roster cut deadline. All NFL teams will have to cut their training camp roster of 90 players down to the top 53, along with filling out a practice squad with 16 players.

Head coach Dan Campbell and general manager Brad Holmes don't have a bunch of major decisions on their hands, with most of the roster set after curating a championship-level squad over the last three seasons, but the back-end spots at certain positions were hotly contested and up for grabs in the month of training camp practices and games.

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Here is some more info on the NFL deadline day and the decisions facing the Lions.

When do the Lions have to trim the roster?

The NFL's deadline to set an initial active roster for the season is at 4 p.m. on Tuesday. This is also the deadline when teams have to decide whether a player will come off the physically unable to perform list or stay on to begin the season, which comes with sitting out the first four games.

Luckily for the Lions, newly-added defensive tackle DJ Reader was activated off the PUP list Sunday, clearing him to return from a torn quadriceps injury before the Lions' fifth game if he's ready to go.

How many players make the roster?

An official NFL roster is comprised of 53 players, meaning the Lions will have to part with 37 players to get down from the 90-player training camp roster.

Who is on the Lions' roster bubble?

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The Lions have most of the roster set, but competitions for depth spots at wide receiver, the offensive line, edge rusher and the secondary. Detroit sat the starters for all three preseason games to let these battles for the backup spots play out on the field.

Behind the starting five on the offensive line, tackles Dan Skipper and Colby Sorsdal are backups on the outside and Kayode Awosika is a backup on the inside. Kingsley Eguakun, Michael Niese and Duke Clemens fought for another potential backup spot at guard or center while Giovanni Manu is a longterm project buried deeper at tackle.

At wide receiver, the Lions wanted someone to step up and emerge behind Amon-Ra St. Brown, Jameson Williams and Kalif Raymond, and undrafted free agent Isaiah Williams made the biggest impression out of all the available options over others such as Donovan Peoples-Jones, who has NFL experience on his side.

The depth behind Aidan Hutchinson and Marcus Davenport at defensive end is another decision point. The options include James Houston, Isaac Ukwu, Mitchell Agude and Mathieu Betts. In the secondary, Brandon Joseph pushed for the last safety spot, potentially ahead of C.J. Moore, while Khalil Dorsey, Steven Gilmore and Kindle Vildor battled for a spot at cornerback.

The roster math will be something to watch as Holmes and Campbell decide how to allocate bodies to different position groups. The Lions will likely keep three quarterbacks — Jared Goff, Hendon Hooker and Nate Sudfeld — taking a potential spot away elsewhere.

What happens to the players who do not make the Lions roster?

The Lions will have to part ways with dozens of players who made the training camp roster before Tuesday's deadline.

If the Lions do not bring back a player who has four years of service time or less (rookie deal equivalent), the player must be placed on waivers. The other 31 teams will have a chance to make a waiver claim on the player ahead of a noon deadline on Wednesday.

If the player clears waivers, or is a veteran that clears the threshold, they will become free agents and be free to sign wherever including potentially returning to the Lions' practice squad.

Who could make the Lions' practice squad?

The Lions can have 16 practice squad players, 17 if the player is in the International Pathway Program (IPP). Campbell said after the final preseason game he and Holmes would be considering players that can challenge the Lions' established players all season in practice while having the potential to step in if there's an injury.

"Do we really think this guy can help us down the road?," Campbell asked rhetorically to explain the Lions' practice squad philosophy. "Is this somebody we can invest in and is going to help us if we need him? If we lose a couple of guys to injuries, can this guy step in, do a good job, play special teams, whatever it is?"

In the last week, Free Press Lions beat writer Dave Birkett pointed out linebackers Abraham Beauplan and Ty Summers, defensive tackle Chris Smith, safety Loren Strickland and quarterback Jake Fromm as potential practice squad targets for the Lions if they clear waivers. The Lions will also see what they can grab from all the other roster cuts to round out the roster, including potentially bringing in a practice squad kicker as Jake Bates insurance.

Jared Ramsey is the sports trending reporter for the Detroit Free Press. Email him: jramsey@freepress.com. Follow him on X at @jared_ramsey22.

This article originally appeared on Detroit Free Press: Detroit Lions roster cuts: What to know as deadline looms