Many things stunted the 49ers from having a better season than they did in 2016. Mostly, it was due to the defense.

The starting unit at the beginning of the season became a depleted mess by week 17. Many of the starters were on injured reserve, and the ones that were put in place couldn’t pick up the slack. It was something that left fans grimacing, as they watched opposing offenses trek down the field to score each and every time.

At this point, it’s important to optimistic about the future and to see who will be installed into the starting lineup on the defensive side of the ball.

Starting Defensive End: DeForest Buckner

The 2016 rookie standout was something to behold. He is a great building block for the defense, and also provides the skill to get at the quarterback; which he showed as he tied the team’s sack lead at six.

Look for him to be an every-down type of player at defensive end. He has a high motor and a nose for getting to the quarterback.

Starting Nose Tackle: Earl Mitchell

The now eight-year veteran will provide the much-needed help at nose tackle that the 49ers need. He will be used to assist in creating lanes for blitzing players to get after the quarterback and ball carriers. Not to mention, to help out in the running game, and to make sure that the defense doesn’t have a repeat of last season.

However, don’t be surprised to see someone like DJ Jones coming in to take over either. The young rookie has both the size and strength to make an impact that the nose tackle position.

Starting Defensive Tackle: Solomon Thomas

The third overall pick in the 2017 Draft will make an immediate presence in his rookie season. The 49ers are hoping for the Stanford product to be the team’s, Michael Bennett, and provide the added toughness to the defensive line.

He has all of the tools and techniques to help him become the player that they want him to be. However, he could fill the LEO role as well. Thomas has the athleticism to take on that position as well, but he would be best suited for the defensive tackle.

Starting LEO: Arik Armstead

It was a toss up between Armstead and Lynch, but Armstead is more used to being in a three-technique than Lynch. He has the right amount of explosiveness and play-style to take over the defensive scheme’s LEO position.

Also, Armstead has a much bigger build and is currently much leaner than Lynch is currently. However, don’t be surprised by seeing Lynch being put into the role of LEO if need be. He still has so much impactful ability to get after the quarterback.

Starting Outside Linebacker: Ahmad Brooks

If there is one thing that 49ers fans know, it’s that the organization can’t stomach letting Brooks go. The 2013 pro bowler has been tied for the team’s sack lead the last four seasons dating back to 2013.

Brooks is a talented pass rusher that has a nose for getting after opposing teams’ quarterbacks. No matter what the 49ers will do they may never get rid of Ahmad Brooks.

Then again, don’t be surprised if rookie, Pita Taumoepenu gets subbed into the mix. Or even, Super Bowl XLVIII MVP, Malcolm Smith. Both have incredible talent that can’t be wasted on the bench.

Starting Inside Linebackers: NaVorro Bowman and Reuben Foster

NaVorro Bowman will never lose his starting spot as the team’s inside linebacker. Unless of course, it’s by injury; again. The all-pro inside linebacker is the leader on defense, and will never be expected to lose his job to anyone.

Foster will be immediately put into the starting lineup alongside Bowman. People have said that the young man is an embodiment of Bowman’s former running mate, Patrick Willis.

Even if one of them gets injured, the team still has Ray-Ray Armstrong to turn to. Who isn’t a bad player to turn to.

Starting Cornerbacks: Rashard Robinson and Ahkello Witherspoon

Robinson was the team’s biggest steal from the 2016 Draft, as he went above expectations to take over the starting outside cornerback role. He will continue taking the next step in becoming a bonafide star at the cornerback position.

The big surprise on the starting defensive unit will be Witherspoon. Not only does he have the necessary speed and length to attack the ball and separate it from opposing receivers, but he is a natural fit in this defensive scheme.

The nickel corner position can still be utilized by players like Dontae Johnson or Will Redmond. However, the most likely candidate to fill in for that role is nickel specialist K’Waun Williams.

Starting Safeties: Jimmie Ward and Eric Reid

It has been reported that Ward will be used as the single high safety in the defensive scheme. He will be returning to his old role that he played back at Northern Illinois as a free safety. This will officially make him the team’s Earl Thomas.

Reid will become the Kam Chancellor to Ward’s Earl Thomas. Reid not only is a great player in coming up in the box to assist in the run defense but will be able to cover the short to intermediate routes.

It’s unsure as to what will happen with Jaquiski Tartt, but he will most likely be used as a dime or nickel corner.