5 Positions Pittsburgh Steelers Must Still Address Before 2015 Season

The 2015 NFL draft is over. Teams have already met for offseason workouts, and minicamps begin in earnest in just a few days. For the most part, the Pittsburgh Steelers roster is stable. Although undrafted players will cycle in and out over the next few months while the roster balloons to 90 men, positional battles will start to play themselves out.

The Steelers still have roster needs, though. Let's take a look at the five biggest ones that remain after the draft.

Defensive End

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Brett Keisel is gone. Cameron Heyward has finally come into his own, but the defensive end position still has a level of uncertainty for the Steelers. The battle will come down to 2014 draft pick Stephon Tuitt and Pro Football Focus' worst-ranked 3-4 defensive end of 2014, Cam Thomas. Even rookie Leterrius Walton could be part of the discussion, especially given how poorly Thomas played against the run last year.

The Steelers have enough bodies on their roster to produce two starters at defensive end for 2015. The question, though, is who will be the one to join Heyward. By the end of 2014, Tuitt had gotten the nod over Thomas and, because of that, could have the greatest chance to win the job this year. But Thomas cannot be ruled out entirely, nor can a push from Walton.

Defensive end might not be the flashiest position, but if the Steelers want to improve against the run, they need to select the right man for the job. Opponents averaged 4.4 yards per rush against them last year; that will be unacceptable for a second straight season.

Backup Quarterback

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The hope is that the Steelers never need to turn to their backup quarterback. But should Ben Roethlisberger suffer any type of injury and has to miss time, they need to be confident that whoever is backing him up can step in with as little drop-off in performance as possible.

In a perfect world, the Steelers would possess a trio of Roethlisberger clones and never have to worry about losing a game because they lost their starter. But that's not the case. Currently, Bruce Gradkowski is the primary backup, with Landry Jones and Tajh Boyd rounding out the depth chart. 

But it's possible, with two years of experience in the Steelers system, that Jones could leapfrog Gradkowski. It's also possible that Jones has reached his ceiling and could lose his roster spot to Boyd.

The backup quarterback discussion could prove to be moot if Roethlisberger can put together a third straight season in which he completes all 16 games. But the Steelers do need to be confident in their backup, which means that they could address the position this summer if they are no longer so trusting of Gradkowski or so patient with Jones.

Running Back

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Counting undrafted rookie Ross Scheuerman, the Steelers currently have four running backs on their roster. Aside from the rookie, they have the ultra-talented Le'Veon Bell, veteran DeAngelo Williams, who was signed as a free agent earlier in the spring and the mostly inexperienced Josh Harris, who had just nine regular-season rushes last year for 16 yards.

Bell and Williams are a perfect pair for the Steelers. And, at first glance, it would seem like the team is all set at the position. However, Bell is slated to miss the first three games of the season because of a DUI-related suspension, leaving the Steelers with few options outside of Williams.

For this reason, they would be wise to expand their running back ranks beyond just four players this summer in order to find someone dynamic enough to partner with Williams while Bell serves his suspension.

Nose Tackle

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Last year, the starting nose tackle was Steve McLendon. According to Pro Football Focus, he played 305 snaps at the position, which indicated that Pittsburgh was rarely in its 3-4 base. But it is still an important position, one that can determine how well the defense stops the run and rushes the passer.

The Steelers drafted a nose tackle in 2014, taking Daniel McCullers in Round 6. McCullers, though, played just 65 snaps as he spent much of the season simply learning and observing. But it's looking more possible that McCullers will see vastly increased snaps in his second year.

Defensive line coach John Mitchell said, via the team's official website, that McCullers "was the guy right from Tennessee; he didn't know what it would take to play on this level. He's been around good football players. He watched how Cam Heyward worked. It got contagious. ... I like where Dan McCullers is right now."

He also said that McLendon "is going to be a better football player" in 2015. Clearly, Mitchell is ready for a battle to play out between McLendon and McCullers this summer at the nose tackle position. So for now, this position is up in the air. They certainly don't need more nose tackles in the competition, at least.

Safety

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Without question, the position the Steelers still need to successfully address is safety. It's possible both free and strong safety positions are up for grabs, with Mike Mitchell, Shamarko Thomas, Will Allen and rookie Gerod Holliman in the mix.

Mitchell was the starting free safety in 2014. He totaled 71 combined tackles and three passes defensed while playing with two torn groin muscles. Allen has been a reserve safety for the team for the last two years (and from 2010 through 2012) and had four starts in 2014. Thomas, a 2013 fourth-round draft pick, spent most of his 2014 on special teams and played just two snaps at safety, per Pro Football Focus. Holliman led the NCAA in interceptions last year with 14 but needs to work on his tackling technique.

It's going to be some time before the safety position is set for the 2015 season. This will be the Steelers' most exciting and long-lasting training camp battle. Though the Steelers have enough players already on the roster to produce two starters, until the depth chart is less murky, this position will remain one of need.