Chris Greenwood hasn't played a down in the NFL, but he could have a big impact on the Lions this year.
In December 2011, the Detroit Lions signed little-known running back Joique Bell away from the New Orleans Saints. Jim Schwartz and Wayne State University fans were familiar with Bell's work, but no one knew what kind of impact he'd have, if any.
He had tons of potential, but there was also a possibility he wouldn't even make the roster.
Division II guys aren't exactly a dime a dozen in the NFL. Plus, the Lions' second-round pick Mikel Leshoure was finally healthy and ready to contribute full-time.
Bell was the ultimate wild card for the Lions and had a breakout campaign in 2012. He proved he belonged in the NFL, and for that, Pro Football Focus recently labeled him their "Secret Superstar".
The Lions have a number of players poised to follow in Bell's footsteps from obscurity to stardom.
They got significantly younger this offseason and have unproven players vying for starting roles who could dramatically impact their success.
These guys are wild cards. They could just as easily rise to stardom or fade into NFL obscurity.
Jason Fox, OT
I alluded to the number of young players that could be wild cards for the Lions this season. However, age isn't the only factor.
Jason Fox is no spring chicken. He's been in the NFL four years, but his sample size is extremely small.
Let me rephrase that—his sample size is zero. Injuries robbed him of his first three years. He spent last season, his first one healthy, buried on the bench behind Jeff Backus, Gosder Cherulis and Riley Reiff.
The Lions held on to Fox, despite his lack of production, because they believed in his potential. With significant turnover on the offensive line, now is his chance to prove they didn't make a mistake.
It won't be easy.
He'll compete with Corey Hilliard for the starting right tackle spot. If he wins, he has to prove he's an upgrade over Gosder Cherilus—a frustrating but solid right tackle for the Lions. If Fox turns out to be the player the Lions believe he is, he'll make everyone forget Cherilus.
Conversely, he could be a dud who loses out to Hilliard or gets injured in training camp once again.
Chris Greenwood, CB
If Chris Greenwood carries business cards, they probably read, "Chris Greenwood: the man, the myth, the legend."
That's because his potential for greatness has clearly been elevated to a legendary status. Many fans are ready to pencil him in as a starter opposite Chris Houston.
It's understandable. At 6'1" and nearly 200 pounds, Greenwood ran a 4.4 40-yard dash at his pro day. Clearly he has the size, speed and athleticism the Lions crave for their secondary.
He seems almost too good to be true.
Unfortunately, he might be just that. Greenwood last played competitive football against Division III talent. He hasn't even practiced against NFL players yet. An abdominal injury robbed him of that, and there's no telling whether his physical attributes will translate to success on Sundays.
He's healthy now and, according to Mlive.com's Anwar Richardson, he's ready to make his second chance count. Only time will tell whether he can hang with the big boys, or if he needs more time to develop.
It's essentially his rookie year, so expectations should be kept low. On the other hand, size and speed can't be taught. Greenwood has those things in spades, and that makes his potential impact very intriguing.
Tahir Whitehead, OLB
Whitehead was drafted in the same round as Greenwood in 2012, and to most his selection was just as big of a surprise.
Unlike Greenwood, Whitehead contributed on a regular basis as a rookie—on special teams. He did well, finishing third in tackles (10) and forcing one fumble according to detroitlions.com. This year he'll compete with veteran Ashley Palmer and fellow second-year player Travis Lewis for the starting OLB position vacated by Justin Durant.
Whitehead has the most upside, though.
He was a pass-rusher in a 3-4 defensive scheme in college, but has benefited greatly from having a year to play special teams and concentrate on learning the Lions' 4-3 wide-nine system.
He's got excellent speed, good coverage skills and is a skilled tackler. His experience in college could result in the Lions using him as a surprise blitzer as well.
Obviously there's a chance that Whitehead gets beat out by Palmer or Lewis. On the other hand, he's got the versatility to not only replace Durant, but upgrade his position.
Ezekiel Ansah, DE
Is there really any doubt that Ezekiel Ansah is the biggest wild card for the Lions this year?
There shouldn't be.
The Lions selected him fifth overall in the NFL draft. Even though there was nearly universal agreement he was a first-round talent, it was all based on potential.
Ansah looks the part of an elite defensive end. He's got the size, length, speed and strength that make defensive coordinators salivate. His physical gifts have drawn comparisons to Giants great Jason Pierre-Paul.
On the other hand, Ansah's potential for greatness is matched only by his potential for being a bust. That's scary for Lions fans to think about, but it's true. His lack of technique and actual on-field football experience makes him a risky proposition to start his rookie year.
Yet start he will.
The Lions really don't have a choice. They lack proven pass-rush talent, and while he might be in the perfect situation to succeed with Gunther Cunningham and Jim Washburn teaching him the ropes, there's no guarantee he'll develop as quickly as Detroit needs him to.
So far, Ansah is right where he should be. He's shown progress and flashes of dominance during OTAs. The biggest plus so far has been his maturity and willingness to learn from his veteran teammates, according to detroitlions.com.
Keep in mind, no one is wearing pads and the competition is light. The real test will come during training camp.
Ansah represents the biggest wild card for the Lions. If he shows significant development in his rookie year he could single-handedly take the defense to new heights. If not, the Lions' pass rush will be woeful and opposing quarterbacks will pick their defense apart.