The 49ers have established good depth this season and managed to keep rolling despite 15 players going on injured reserve since training camp.

The defensive line has been an area of great depth since the additions of Dee Ford in a trade and Nick Bosa in the draft during the offseason, but that unit has taken some recent hits.

The possibility of the 49ers adding some depth leads off this edition of the 49ers Mailbag.

Do you see the 49ers trying to claim Janoris Jenkins And Terrell Suggs? — Chad (@Bruh_Moment453) December 14, 2019

I do not see any possibility -- or reason -- for the 49ers to put in a waiver claim for 31-year-old cornerback Janoris Jenkins. But Terrell Suggs is a different story.

The 49ers have seen their depth at edge rusher diminished with season-ending injuries to Ronald Blair and his replacement, Damontre Moore. Also, Dee Ford is not expected to play in the final three games of the regular season. Ford’s hamstring injury could carry over into the postseason, too.

Therefore, it would make sense for the 49ers to claim Suggs, whom the Arizona Cardinals waived on Friday. The problem is that the 49ers are No. 31 in the priority claim list. So, 30 teams would have to pass on the veteran.

As if a reminder is needed, the list of teams in front of the 49ers in the order of waiver claims includes the Seattle Seahawks and Los Angeles Rams. It would not shock me if either (or both) put in claims for Suggs to prevent the 49ers from getting him. If that were the case, and no other teams submitted a claim him, Suggs would end up with the Rams.

As for Jenkins, whom the New York Giants waived Friday, whose spot is he going to take? Not Ahkello Witherspoon. Not Emmanuel Moseley. And Richard Sherman is due back soon. The 49ers have a good thing going, and I don’t see them going after Jenkins.

Both Suggs and Jenkins -- and the rest of the football world -- will find out Monday. That’s when the waiver-claiming period ends for both players.

https://twitter.com/YouKnow_1993/status/1205778367049588738

While in his 30s, 49ers coach Kyle Shanahan always stayed with the hot player. He turned 40 Saturday, but my guess is Shanahan will be the same person in his early 40s.

In recent weeks the hot running back was Raheem Mostert. He leads the team in rushing yards (608) and rushing average (6.0 yards per carry). He has never started a game in his NFL career, but when the 49ers were in a do-or-die situation against the New Orleans Saints, Mostert was on the field.

That tells you all you need to know.

Has Mostert been (understandably) taken off special teams duty? Because it sure felt that way last week. — Derek Gray (@malbekh) December 14, 2019

The 49ers believe Mostert is one of the best special-teams players in the NFL. I tend to agree with that assessment. He is now producing like one of the top running backs in the league, too.

So, yes, with the more he’s asked to do on offense, the more it seems he is pulled away from special-teams coordinator Richard Hightower. But, he still has a role on special teams.

Last week against the Saints, Mostert played 38 snaps on offense and was on the field for 16 plays of special teams. He is playing a little bit less on special teams than typical, but the 49ers still use him in that phase of the game because he is so darn good.

Do you see the Niners using the franchise tag on Armstead next year? Who do you think will most likely be the cap causalities? — Ernest Vasquez (@ErnestVasquezJr) December 14, 2019

That’s a difficult one, but I think the price might be too high to retain Arik Armstead on a one-year franchise deal.

Remember, this is a team that hopes to be able to sign DeForest Buckner and George Kittle to long-term extensions.

It’ll cost the 49ers approximately $18 million to place the franchise tag on Armstead. Unused cap money rolls over, so that would be $18 million fewer dollars to pay out elsewhere.

As for cap casualties, I don’t see any way the 49ers can retain running back Jerick McKinnon at his scheduled salary, and there is no way they will keep wide receiver Marquise Goodwin -- whatever the price.

With so many players out on IR. Why does the team still keep 3qbs. Couldn't they use that extra roaster spot if a backup isn't working out? — Big Joe 925 (@joedawg49) December 14, 2019

The reason the 49ers have kept both Nick Mullens and C.J. Beathard behind Jimmy Garoppolo is because they honestly believe they are among the team’s 53-best players. They view Mullens and Beathard as valuable assets to the organization.

Also, remember, only 46 players suit up for games. So it really does not matter if they keep a player at another position on the 53-man roster because that player would not be suiting up for games, anyway.

Which of coach Shannan’s staff do you believe will get attention from other teams? — Rodrigo Sanchez (@RigoSanchezC) December 14, 2019

Certainly, Robert Saleh will get some attention for head-coaching openings. His work as 49ers defensive coordinator should get him in the door as a candidate, and he will undoubtedly be impressive in the interview process.

Two individuals who could be candidates to become offensive coordinators with play-calling responsibilities are passing-game coordinator Mike LaFleur and run-game coordinator Mike McDaniel.

Shanahan declined to grant permission to Green Bay for LaFleur and Arizona for McDaniel to hire those two assistants because he considered those coaching positions to be lateral moves. The head coaches in both of those places call the offensive plays, just as Shanahan does with the 49ers.

I know it’s the Falcons, but with the injuries on defense, any chance of this being a trap game? — graham (@grahamuel382) December 14, 2019

I do not believe the 49ers are going to breeze through this game because of the injuries, as well as the difficulty of bouncing back from such an emotional victory. Also, the Atlanta Falcons are playing better football. It is not going to be easy.

The 49ers has good back ups on all positions. Now 15 players are gone for the season. How hard is it to win the division?? — alfonso (@cocorito1965) December 14, 2019

It will be difficult, no doubt.

But I think you also have to look at the players who have been lost for the season due to injuries. Here’s how I rank the importance of the players lost to season-ending injuries:

1, Nose tackle D.J. Jones

2, Center Weston Richburg

3, Linebacker Kwon Alexander

4, Edge rusher Ronald Blair

The remainder of the guys on injured reserve were not going to be big factors down the stretch of the season.

Those four listed above are all very good players, but I believe as long as the rest of the injured guys who are going to miss the game Sunday -- Richard Sherman, Jaquiski Tartt, K’Waun Williams, Jullian Taylor and Ford -- can return in time for the playoffs, the 49ers should be fine.

[RELATED: Saints DB who grabbed Kittle's facemask on late play fined]

Who sits game day? Pettis or Matthews? — whoissparta (@jniner37) December 14, 2019

Dante Pettis, I would assume, will be in uniform. He has been cleared to play after sitting out two games with a knee injury.

Jordan Matthews was signed this week to be the 49ers’ sixth receiver, so I would not envision him suiting up for the game.