Buying or Selling NFL Preseason's Biggest Breakout Stars in 2015

The NFL preseason is a tremendous opportunity for players to break out and prove they’re ready to be major contributors this year. While some young players are expected to take the next step in development, others emerge out of the blue. Teams that strike gold with an unheralded backup breaking out greatly benefit from an affordable surprise.

But not every preseason star will continue to have great success in the regular season. Competition ramps up once the games count, as the rosters are trimmed to 53 from 90. The sharp jump in quality of play can wash out preseason stars because they’re no longer facing third-stringers.

We’ve seen some excellent play from young players this preseason. Not all of them will continue to be impactful stars throughout 2015, though. Some may have to wait another season to flourish in the regular season due to lack of opportunity or needing more consistency.

We’re buying and selling whether the top five breakout stars from preseason will continue to show out in the regular season. Can these young players prove to be a consistent, week-to-week threat? That’s what we’re attempting to answer.

Amari Cooper, Oakland Raiders

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Amari Cooper, the fourth overall pick in the 2015 NFL draft, undoubtedly impressed in the preseason. Expectations for Cooper are lofty after that No. 4 selection. The good news for the Oakland Raiders is that Cooper delivered on his draft status in the preseason.

Cooper’s NFL-readiness was never in doubt. He showed it in limited first-team snaps, earning eight receptions for 124 yards. Although he didn’t catch a touchdown, he did have two 20-plus-yard receptions.

Oakland is desperate for those big plays. Its 2014 offense was too limited because of a bad playmaking core. We’re definitely buying that Cooper will help transform this unit and have a great rookie campaign.

Verdict: Buying

Jeff Janis, Green Bay Packers

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As soon as Jordy Nelson suffered a torn ACL, the Green Bay Packers’ receiver depth plummeted. Besides Randall Cobb and Davante Adams, the Packers lack any type of proven playmaker at the NFL level. That leaves second-year man Jeff Janis as one of the young players expected to take on a massive role.

Janis was productive at Saginaw Valley State and tested as a wonderful athlete at the 2014 NFL combine. But he is as raw a receiver as you’ll ever find. His route tree consists of slants and go routes, with little quality in between.

Janis was fairly productive against third-team defenses in the preseason, but he’ll be facing a major jump in competition in the regular season. Playing with Aaron Rodgers will certainly boost Janis’ statistics, but we’re selling that his talent is ready for a big-time role in 2015.

Verdict: Selling

Matt Jones, Washington Redskins

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The Washington Redskins invested a third-round pick into Matt Jones in the 2015 draft, and the preseason proved why that was a good move. Jones is a physical specimen at running back, measuring 6’2”, 231 pounds at the NFL combine. His movement ability for someone his size is impressive.

Jones isn’t just a workout warrior, though. His on-field play through three preseason games demonstrated a violent running style and his ability to make defenders miss. He amassed 139 yards on 20 preseason carries.

It may not be long before Jones is cutting into Alfred Morris’ workload. Jones is already more explosive and a better receiver. He has real star potential with the way he runs the ball.

Verdict: Buying

Alejandro Villanueva, Pittsburgh Steelers

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Alejandro Villanueva is probably a name that most do not know at this point. The 6’9”, 340-pound offensive tackle was actually a tight end for Army and weighed 245 pounds just one year ago. Pittsburgh snatched him from Philadelphia last year and converted him to tackle.

His first season at tackle has been excellent so far. Villanueva is nimble yet powerful, which is perfect for a power gap scheme. The Steelers won’t need him to start this year, but he’s fully capable if he has to.

Talent is not why we’re selling Villanueva for 2015. He simply won’t need to play unless injuries strike. But he’s effective enough that other teams should offer a Day 2 pick in the 2016 NFL draft to snatch him away from Pittsburgh. He’s that good.

Verdict: Selling

Zach Zenner, Detroit Lions

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One year after fostering an expensive, broken-down and unproductive backfield, the Detroit Lions have a much brighter situation. Rookie running backs Ameer Abdullah and Zach Zenner have brought a dynamic breath of fresh air to this running game. Zenner has especially been impressive with his extended time on the field.

Through three preseason games, Zenner had 25 carries for 162 yards and a touchdown. He added six receptions for 60 yards and another touchdown. He’s locked up his roster spot.

The question for Detroit is whether it uses Zenner over veteran Joique Bell. Considering how Bell has been ravaged by injuries and Zenner is fresh, a strong argument should be made that Zenner should play over Bell. There’s no reason to think he will not continue his effectiveness in the regular season.

Verdict: Buying

Ian Wharton is an NFL Featured Columnist for Bleacher Report. 

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