3 rising players stepping into big shoes in 2015

Pundits always miss at least one big storyline in their preseason prognostications about which teams will play major parts in the hunt for the national championship. There are numerous reasons for this, including the fact that making predictions about complex systems that involve humans is generally an impossible art. One such factor that always trips up the preseason pollsters is the cyclical nature of college football rosters.

You'll always hear notes like "team X is returning 16 starters!" as evidence for why a particular team is expected to have a big season. The sheer number of returning starters is often less helpful than noting which players return. When a team returns players that were a focal point of their team's identity and strategy this is often a good sign while returning a high number role players doesn't always indicate another big year.

If this wasn't complicated enough to suss out, you routinely see young players that have barely even seen the field make a leap and become household names. Manziel and Winston won Heisman trophies with such seasons, Ohio State's Darron Lee came alive in the 2nd half of 2014 as the Buckeyes surged into the playoffs, anticipating story lines like this is very difficult.

With that said, here are a few less well known players stepping into big roles or looking to build on limited success that could shape the 2015 football season for some big time contenders.

Nick Vannett: Tight End, Ohio State

Jeff Heuerman was secretly a lynchpin to Ohio State's run game success over the last two seasons. After playing a major role as the H-back/TE for the 2013 team, Heuerman and a single Buckeye offensive lineman were the only returning starters for Urban Meyer in the trenches from a dominant group that also lost the starting QB and tailback.

In Ohio State's power-spread, the H-back plays a huge role in providing a mobile blocking surface that allows the offense to over-stress different parts of the defensive front and have tremendous versatility with the different ways they can run their staple inside zone and power schemes. Heuerman excelled here while a young OL rounded into the form they took in the 2015 playoffs.

A good tight end is hard to find, much less replace, but the Buckeyes were forced to begin the replacement process for Heuerman during the playoffs and turned to redshirt senior Nick Vannett, who was exemplary in his snaps and even scored in the national title game.

The best hope for a Buckeye falloff in 2015 was that they'd fail to replace the quietly brilliant Heuerman...but with Vannett, they may be getting an upgrade. In the realm of angle blocks, he's Heuerman's equal at winning battles with defensive lineman:

This wham block is actually a difficult concept to execute as the tight end has to maintain enough of a lane for the running back to fit through while taking on a defensive tackle. At 6'6" 265, Vannett has the strength to win these battles with rival behemoths in the trenches.

There are some other spread teams around the nation that would love to have a powerful H-back player like this that could give them some versatility and physicality in the box and be happy if he couldn't do much of anything else...but Vannett can.

The Buckeyes are totally comfortable flexing him out wide where he's fairly quick as a route runner and has good, reliable hands.

It seems unfair that a team returning three quarterbacks, a running back who dominated the playoffs, and so many other important players would receive an upgrade at their most essential ancillary position but that may be exactly what's happening in Columbus. If so, this may be one of the biggest events of 2015 that no one ever talks about.

Eddie Jackson: Strong Safety, Alabama

The succession of future professionals at Alabama's safety positions is an impressive line that runs through the Nick Saban era. It started with Rashad Johnson, who passed the torch to Mark Barron, who handed it off to Haha Clinton-Dix, who gave it to Landon Collins, and now the Tide are looking to Geno Smith and converted cornerback Eddie Jackson to step into the spotlight.

The strong safety position in the Alabama defense is a demanding one as it calls for a rangy playmaker who can fill the alley and be the final piece to an impregnable wall against the run game. Landon Collins was tremendous in this role and could make tackles near the line of scrimmage on plays where he started the snap as a two-deep safety:

Take notice of the fact that the nickel (now starting free safety Geno Smith) allows the ball outside of him, which is a big no-no for a force defender, and Jackson has to change course and pursue the ball out wide but still makes the tackle at the line of scrimmage.

That's the kind of range and tackling ability that Eddie Jackson is being charged with replacing.

Eddie Jackson has already served the Tide as a starter in both his freshman and a sophomore seasons while at cornerback where his size (6'0" 194 pounds) is prized by Nick Saban for his bump and run press coverages designed to impose physicality and deny opponents easy yardage in the quick game.

Of course, the consequence of Saban's love for press coverage is that the safeties need to be rangy in order to cover up anything that slips through the cracks. After Bama's recent success recruiting at cornerback it is possible for the Tide to attempt and make use of Jackson's size and athleticism in this role.

The Alabama spring game seemed to indicate that moving Jackson to strong safety and combining him with new starting nickelback Maurice Smith has left the Tide secondary less experienced on the back end as they gave up an early TD pass on a 4th and 10. However, if these new charges are able to wield their natural athleticism in the middle of the field then Alabama shouldn't struggle to pass the torch of professional-level DB play at the position.

Kolby Listenbee: Wide Receiver, TCU

Listenbee actually served a valuable role in the Horned Frog offense in 2014 as one of the main targets in their passing game with 41 catches for 753 yards and four touchdowns. As a legitimate track star who has clocked times of 10.12 in the 100 (wind aided) and 20.61 in the 200, Listenbee's primary role last season was to run under Trevone Boykin deep lobs:

With a hop step to the right before planting and blasting by on the left, Listenbee creates enough separation here to accelerate and then it's all over. He rarely did much else in 2014 save for run deep or catch screen passes underneath.

The role of taking the top off the defense was a very important role for an offense that was geared largely around Boykin's talents. Most of the time the Frog offense consisted of attacking the middle of the field with the run game and then using Boykin's arm strength to punish defenses that concentrated numbers in the boxes with quick throws outside the hash marks. The abilities of Listenbee to get open deep or Doctson to win jump balls helped prevent teams from playing single-high safety coverages to even up the numbers and eliminate easy space for Boykin to operate in.

With Deante' Gray and Josh Doctson injured in the spring, Listenbee had the chance to develop as primary option for Boykin and the passing game. For him to become a dominant option that launches the TCU offense from S&P's 16th best offense into the top 10 or top five will require that he become a reliable option on concepts such as this one:

Using his quickness to get open underneath and run reliable timing routes and tunnel screens would elevate the Frog offense to another level. As soon as Listenbee becomes a player that requires man coverage underneath with a deep zone defender sitting on top than the rest of the TCU offense becomes indefensible.

Given all of their losses on defense that's a leap that this team probably needs him to make in order to get their shot at the college football playoffs.

Undoubtedly there are some young players out there on teams that are just below the national conscience, ready to make leaps and have seasons that will themselves and their programs on the map. But even amongst the known contenders, these three names are likely to be crucially important in whether the unexpected rise of a lower ranked team comes at the expense of one of these contenders.