Kelley L Cox-USA TODAY Sports

Kelley L Cox-USA TODAY Sports

Anytime a team rebuilds it's roster, it's going to be faced with ups and downs. Expecting results right away isn't necessarily realistic, and getting in the win column can be difficult. Even though going through growing pains is inevitable, it's important that you can start to see things at least trending in the right direction, and cornerstone players start to identify themselves. I think that's where the San Francisco 49ers are in terms of their defense. While some holes still need to be filled, it looks like the arrows pointed upward for this unit. Here's a look at five burning questions facing the Niner's defense as we enter 2016.

1) How good can Arik Armstead and DeForest Buckner be?

The 49ers were one of the best defenses in the league from 2011-2014, and a big reason for that was the play of 3-4 ends Justin Smith and Ray McDonald. In an effort to replicate that success, the team has spent their last two first-round picks on Armstead and Buckner, and both look the part early on.

Armstead was a big swing or miss prospect coming out of college, but if early returns are any indication, the Niners may have hit a homerun. Armstead had a strong rookie year in 2015, recording 38 total pressures in 384 snaps. Per Pro Football Focus, his pass rush productivity (12.3) was the highest of any 3-4 end who played at least 155 snaps. Armstead's followed that up with a strong camp, and seems poised to play a huge role on the defensive front this season.

As far as Buckner, he may have been the most NFL ready defensive player in the 2016 draft. PFF ranked him as the best interior defensive lineman in the nation last year with a plus-73 grade, which was the highest total in some time. Overall, he registered 67 defensive pressures, nine more than any other interior player. Look for the 49ers to move Buckner around a bit to take advantage of his diverse skill set.

While you have to be careful not to lean too much on players so early in their development, it's easy to get excited at the prospects of having Armstead and Buckner for the foreseeable future. The two could combine to be a special pairing and anchors for the defense for a long time.

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2) Who's going to rush the passer?

Aaron Lynch's four game suspension is a killer, as he was quietly becoming one of the top pass rushers in the league. Sacks only tell part of the story, and the 6.5 Lynch had last season don't begin to show just how disruptive he really was. PFF ranked Lynch in the top 10 in pass rush productivity in 2015, along with names like Von Miller and Justin Houston. In place of Lynch, the team will have to hope that Ahmad Brooks can find the fountain of youth, and Eli Harold and Tank Carradine are able to make significant jumps. Even when Lynch returns, someone will have to hold up their end on the other side. Could rookie Ronald Blair be someone who seizes the opportunity?

The wild cards here though could be Armstead and Buckner (see the reasons stated above). With all of the attention that could be paid to those two, it could easily open up opportunities for their teammates, and jump start what would have otherwise been an uninspired pass rush.

3) Who will line up next to NaVorro Bowman?

In what's become a very interesting camp battle, the 49ers continue to search for the best option alongside perennial All-Pro Bowman. Considering the team's first unofficial depth chart listed Michael Wilhoite, Ray-Ray Armstrong and Gerald Hodges all as starters, it's safe to say the competition is wide open. Wilhoite has started most of the last two years, and done a solid job recording 87 and 85 tackles respectively.

Hodges was acquired last October in a trade with the Minnesota Vikings, and he ended up starting four games for the Niners. A former fourth-round pick, he's the only one of the competitors who was actually drafted. Armstrong is the unknown here, as he's mostly played special teams, but San Francisco must really like something about his game as they've given him a huge opportunity.

How this shakes out is anyone's guess, but Wilhoite might be the safe bet given his experience and mostly steady play.

4) Is Jimmie Ward ready to break out?

After a shaky rookie campaign in 2014, Ward really came on towards the end of last season, and was ranked as one of the top corners in the league down the stretch. From Week's 13-16, Ward allowed a 44.6 passer rating, which was seventh best out of 109 corners. PFF ranked him the third best corner overall during the last five weeks of the regular season.

Realizing that Ward was becoming one of his best players, new defensive coordinator Jim O'Neil moved him from the slot in sub-packages to an every down role on the outside. While it will be interesting to see how Ward adjusts to his new role, the 49ers obviously have a lot of faith in him, and this could be the year that he finally justifies his first-round selection.

5) Is Eric Reid the long-term answer at safety?

While the 49ers did pick up Reid's 2017 option back in May, the former first round pick is entering a very important season. Reid looked like he could be a star after making the Pro Bowl as an alternate following his rookie year, but his play has regressed some since then. While he's still a good player, there's reason for concern about which way he's headed.

Reid's sustained multiple concussions since entering the NFL, and it's fair to ask if he's playing a little more cautiously these days (not that anyone could really blame him). He also failed to record an interception last season, after pulling down seven over his first two years. You could argue that's Reid's drop in play could have something to do with the 49ers' declining pass rush, which has gotten worse every year he's been in the league. They've gone from 18th, to 21st, to 29th in the in sacks over Reid's three years. Still, if the Niners are going to commit long term to Reid, he'll have to show that he's closer to the guy they saw in 2013 rather than 2015.

Al Sacco has been covering the 49ers since 2013, and has had his work used by national outlets such as ESPN and USA TODAY. If you'd like to reach Al with a media request, please contact him via Twitter @AlSacco49