5 Pittsburgh Steelers Players Who Should See Their Roles Expand in 2015

Change is a constant force in the NFL, and there's no greater example of this than this time of year, nearly one month removed from the start of free agency and nearly one month away from the start of the draft. Rosters are a work-in-progress this time of year, though some hints emerge about expectations for individual players or position groups.

With that in mind, here are five Pittsburgh Steelers who appear poised for expanded on-field roles in 2015. Whether coming about from a depth chart shuffle, a vacancy at a starting position or as a reward for great play in 2014, these are the players who will see their playing time increase this year.

S Shamarko Thomas

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It's a matter of when and not if strong safety Troy Polamalu is no longer on the Steelers' roster. Whether it comes via Polamalu being released from his contract or him choosing to retire, it doesn't matter—it's time for the Steelers to move on.

And one player that will be a major part of this transition is Shamarko Thomas, a fourth-round 2013 Steelers draft pick. Thomas has spent most of his time in Pittsburgh playing on special teams—he played only two defensive snaps in 2014, according to Pro Football Focus. But now it appears it may be time for him to step up and take on a starting safety role, the position the Steelers ultimately drafted him to play.

It's possible the Steelers may move Mike Mitchell from free safety to strong safety. But that doesn't mean Thomas will be shut out from the field for another year. Whether he would take up the mantle of free safety, push Mitchell for playing time at strong safety or work as part of a defensive backfield rotation, Thomas is poised to do more than just special teams this year.

LB Jarvis Jones

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This is a crucial season for Steelers outside linebacker Jarvis Jones, as it's the first one in which he'll truly get his shot to prove he was worth his team's 2013 first-round draft pick. In two seasons, he's amassed just three sacks and 58 combined tackles, but he also missed nine games in 2014 with a broken wrist.

Now, the circumstances are such that Jones will have to play more than the 237 snaps he did in his injury-marred 2014 or the 646 snaps he played in his rookie year. He's one of just three outside linebackers currently on the Steelers' roster, and even if another is added via the draft, he'll still play a major role in Pittsburgh's pass rush.

Currently, Steelers general manager Kevin Colbert sees Jones competing with veteran James Harrison for the starting right outside linebacker position, though it is equally as possible he tries to push left outside linebacker Arthur Moats for playing time as well. 

No matter where Jones ends up on the depth chart, it's clear the Steelers need more from him this year than they've gotten in his last two. Pass rush is an important component of the Steelers' defensive philosophy. This year Jones will get the opportunity to prove his body, technique and experience level are where the Steelers need them to be in order for him to be an effective source of quarterback pressure.

WR Martavis Bryant

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Last season, 2014 fourth-round Steelers draft pick Martavis Bryant didn't take the field until Week 7. However, what he accomplished once he was called up to the active, game-day roster was impressive—on just 306 snaps played and 26 catches on 49 targets, he totaled 549 yards and eight touchdowns. He had a per-catch average of 21.1 yards and 164 yards after the catch.

The head-turning performance now has Bryant squarely set for increased playing time in 2015. In fact, offensive coordinator Todd Haley says Bryant will be in competition with Markus Wheaton for the Steelers' No. 2 receiver job.

In speaking with the Pittsburgh Tribune-Review's Mark Kaboly last month, Haley said, "We are looking for [Bryant] to come in and make a push against Markus Wheaton for that No. 2 spot and continue give us big-time production, specifically in the red area where a big target like that can make a big impact."

Even if Bryant does not beat out Wheaton for the No. 2 spot on the wide receiver depth chart, expect him to be active and on the field for all 16 games. Given that wasn't the case in his rookie year, then it's apparent Bryant is destined for an expanded role, one way or another.

LB Ryan Shazier

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The Steelers' first-round draft pick from 2014, linebacker Ryan Shazier, came to the team possessing good instincts and even more impressive speed. However, he lacked bulk and also suffered injuries to his knee and ankle that saw him go from a starter in the team's first three games to a situational backup by the season's end.

As such, Shazier amassed only 36 tackles, two tackles for a loss and one pass defensed in his rookie year. This year should prove to be different. Steelers head coach Mike Tomlin predicts not just an improvement in Shazier's understanding of the defense but also an improvement in his physical makeup, particularly in adding bulk to his frame.

Tomlin said at the NFL owners' meetings last month that, "I often refer to Lawrence's [Timmons] physical growth and development when I talk to Ryan Shazier. Lawrence's body was very similar to Ryan's when we drafted him. He was a 20-year-old third-year junior when we drafted him...When I pull out some 2007 and 2008 tape all of those young guys generally laugh at how small Lawrence looks."

Tomlin also added that, "[Shazier's] a third-year junior when we drafted him. We've had a great deal of success with acquiring those third-year type players...There are plenty [of] examples of some of our most premier players being third-year guys when we drafted them so we expect him to grow in all areas and have the type of significance some of those others have achieved."

The Steelers aren't at a loss for interior linebackers. But that doesn't mean Shazier won't see his role increase—especially if he can both gain bulk and stay healthy.

CB Antwon Blake

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No Ike Taylor and no Brice McCain means cornerback Antwon Blake will see significantly more playing time this season than the 275 snaps he played in 2014, regardless of whether the Steelers draft another cornerback (or two) this year.

Blake ultimately relieved Cortez Allen as a boundary cornerback, with Blake working in the slot. This year, Blake and Allen will battle for Taylor's old job, with one likely headed to slot cornerback barring any competition that arises in the draft. Blake totaled 42 tackles, six passes defensed, one interception, a forced fumble and a fumble recovery, all while clocking in at only 5'9" and 198 pounds.

Blake makes up for his lack of size by having good technique and blazing speed. There's a reason he not only pushed Allen initially to sub packages and then to the bench. Blake could spend 2015 as a full-time starter for the first time in his career.