Johnny Manziel and many other players had stellar seasons in 2012, and a lot of factors contributed to that.
For example, Alabama's offensive line made things easy for AJ McCarron, and Oregon's running backs opened things up for Marcus Mariota.
The NFL draft has once again laid waste to many college teams. The draft is taking several star offensive linemen and quarterbacks, and both those positions are major factors in the stat lines of the offensive skill players.
The following slides break down why Manziel and 25 others will not meet the stat bars they set in 2012.
*All draft information is from CBSSports.com.
Ryan Grant had a great season in 2012, despite Tulane's horrible lack of success on the field. (The Green Wave finished 2012 with only two wins.)
Grant will only be facing one major hurdle in 2013, but it is one of the biggest issues that can face a receiver. Tulane's quarterback, Ryan Griffin, is on his way to the draft, where he is projected to be taken in Round 7.
Grant will need to adjust to a whole new configuration of timing, speed and route running to repeat his stat line from last season. His stats will fall enough in the early part of the season that he won't be able to make up for the drop in the latter portion.
Stat line from 2012: 76 receptions for 1,149 yards and six touchdowns.
Alex Amidon might benefit from better play-calling now that Frank Spaziani no longer in charge of the Boston College Golden Eagles,.
But it's more likely that Amidon will struggle without the benefit of Emmett Cleary and John Wetzel on the offensive line.
They aren't extreme losses, but both are NFL-quality offensive linemen and should get picked up on the last day of the draft in April. Without 40 percent of his offensive line, the first half of the season will be difficult for Amidon.
While Amidon is waiting for the quarterback to get comfortable with the new crew, his stats will suffer. He should come on strong in the second half of the season, though.
Stat line from 2012: 78 receptions for 1,210 yards and seven touchdowns.
Nevada had a good season in 2012, and the Wolf Pack finished in the top half of their new conference in the process. Cody Fajardo was a big part of that, as was Stefphon Jefferson.
Jefferson is departing for the NFL, so there won't be as big a decoy to take the focus off Fajardo. The Wolf Pack are also losing offensive linemen Chris Barker and Jeff Nady this offseason.
With two NFL-caliber linemen gone, Nevada will have some adjustments to make. Since Jefferson won't be there to help, the stat lines will suffer a bit. After things settle down a bit, the Pack will be just fine, but those are three huge losses for Nevada to overcome.
Stat line from 2012: 246-of-367 for 2,786 yards, 20 touchdowns and nine interceptions. He also had 190 carries for 1,121 yards and 12 touchdowns.
BYU finished last season 8-5 with close losses to Utah, Boise State, Notre Dame and San Jose State. San Jose State was a six-point loss, but the other three were by a field goal or less.
Cody Hoffman did more than his fair share in 2012, but he will be hindered by the offensive line and a new quarterback in 2013. Taysom Hill, the new quarterback, is losing two of his protectors, and one of them may go as highly as the sixth round.
Football games are won in the trenches, and replacing linemen like Braden Hansen and Braden Brown is not easy. The new starters almost always experience growing pains, and the quarterback usually feels the pain directly. Nelson will either take some sacks or be forced to throw before he's ready.
As a result, Hoffman's stats will take almost as big a hit as the signal-caller's.
Stat line from 2012: 100 receptions for 1,248 yards and 11 touchdowns.
Carlos Hyde had a good season in 2012. Ohio State had a perfect regular season, and Hyde was a big part of that.
Hyde is up against a 4-star recruit for playing time in 2013, and he will win the battle early on. As the season progresses and Ezekiel Elliot gains experience, Hyde will gradually see fewer carries.
Tackle Reid Fragel will further complicate the matter by entering the NFL around Round 5. Ohio State will be in its second season under Urban Meyer, and that will spell success for the team as a whole.
However, Meyer's spread offense will take some of the burden off the tailbacks, and Hyde's stats will dip as a result. Ohio State may win the Big Ten title, and the Buckeyes may even make it to the BCS National Championship Game, but Hyde won't have as great of a statistical season in 2013.
Stat line from 2012: 185 carries for 970 yards and 16 touchdowns.
Noel Grigsby is a bit of an unsung hero for the San Jose State Spartans. (Of course, the Spartans are a bit unsung themselves.) He was the team's leading receiver in 2012 with 550 more receiving yards than any other Spartan.
Grigsby will be hard-pressed to repeat his 15.9 yards-per-catch average due to the fact that he will be isolated and covered by every team's best man. Don't mistake his comparatively limited production for failure, though.
He is a talented receiver who will absolutely make anyone pay for the slightest mistake. The Spartans will be adjusting to the loss of a fourth-round offensive lineman in 2013. David Quessenberry's presence will be missed, but there's no reason the team can't move forward.
It will just take a little time to replace a player of Quessenberry's ability.
Stat line from 2012: 82 receptions for 1,307 yards and nine touchdowns.
Kent State is losing Brian Winters in the top half of April's NFL draft, and his absence will hit the running game the hardest.
Kent State rushed for 3,161 yards and passed for 2,275 back in 2012, and the Golden Flashes will need to lean on the passing attack in 2013 while the line shakes itself out.
Trayion Durham will suffer the most, as he will still be the go-to tailback in terms of carries. He's the every-down back for the Flashes, and his most talented front line blocker will be gone.
His numbers will suffer, but that's simply on the individual level. Kent State can overcome the loss of one offensive lineman to have a great shot at another 10-plus-win season in 2013.
Durham will just have to settle for around 4.5 yards per carry instead of 4.8 along the way.
Stat line from 2012: 276 carries for 1,316 yards and 14 touchdowns.
The other Kent State man who can expect to feel Brian Winters' departure is Dri Archer. He was the better yards-per-carry running back in 2012, but he didn't have nearly the number of carries as Trayion Durham.
Archer averaged a mind-blowing 9.0 yards per carry in 2012, and opposing defenses will do all they can to stop him from gashing them for almost a first down per attempt.
Whether the Golden Flashes lost an offensive lineman is beside the point for Archer. When you almost average a first down every time you touch the ball, you can expect some parts of your stat line to take a hit.
It may not be the wisest thing to do, but players have to stop the guy they know can beat them, even if it turns out that there are others on the field that will still gouge them. After all, it doesn't make sense to let a guy as talented as Archer just win the game on his own.
Stat line from 2012: 159 carries for 1,429 yards and 16 touchdowns.
Marcus Mariota's playing style is similar to Johnny Manziel's.
There are three major factors that will cause Mariota's stats to fall in 2013.
- He's under a new head coach, and nobody is Chip Kelly except Chip Kelly.
- Mariota is also facing a Pac-12 schedule that has seen him play for a solid year, so the enemy will be better prepared this time around.
- The final piece of the puzzle is Kyle Long. He's an Oregon offensive lineman that's expected to go in Round 2 of the NFL draft.
Those are three big hits to Mariota's plan of attack.
With a new head coach, stiffer competition and less protection, Mariota will need to spend part of 2013 acclimating himself to his new environment. As he figures things out, his stats will not be as pretty.
Of course, with an average margin of victory of 28 points, his stats can afford to fall. The Ducks can still make it to the national championship game even with the drop, as long as he doesn't falter against Stanford this time around.
Stat line from 2012: 230-of-336 for 2,677 yards, 32 touchdowns and six interceptions. He also rushed for 752 yards and five touchdowns on 106 carries.
Mike Evans was a freshman wide receiver for Texas A&M during the 2012 season. He helped Johnny Manziel win the Heisman, and he helped the Aggies win all but two games last year.
The Aggies even asserted a newfound dominance over the Oklahoma Sooners in the Cotton Bowl to put the exclamation point at the end of the season.
Texas A&M is a title contender on the conference and national levels, and Evans was a valuable contributor to that success. The problem? So was Luke Joeckel.
Joeckel is the No. 1 offensive tackle in the draft, and to say he's expected to go in the first round is an understatement. Joeckel will not be there to protect Manziel, and the receiving game will suffer.
Manziel is a brilliant scrambler, and he can make huge plays at any moment. However, there will be a weak link on the line, and the SEC defenses will exploit that until A&M can get its bearings.
Evans will have a good season, but he'll have to wait for his junior year to put the icing on his NFL draft resume.
Stat line from 2012: 82 receptions for 1,105 yards and five touchdowns.
Devin Street and the Pittsburgh Panthers came close to a winning season. In fact, they lost in triple overtime to the Notre Dame Fighting Irish, the eventual BCS title game loser, late in the 2012 season.
Street faces one major hurdle for the 2013 season that will hurt his numbers a good bit: Quarterback Tino Sunseri is leaving the program during the offseason, since he was a senior in 2012.
When you're missing the quarterback that you built your rhythm with, a drop in stats is expected. Unfortunately for Street, 2013 will be his senior season. He will need to produce to prove that he is worthy of consideration by NFL squads.
If he plays his cards right, he could be a late-round pick on Day 3 in the 2014 cycle.
Stat line from 2012: 73 receptions for 975 yards and five touchdowns.
J.D. McKissic takes the field again for Arkansas State in 2013. This is the same Arkansas State that's won 10 games in each of the past two seasons.
Arkansas State will say goodbye to Ryan Aplin during the offseason, and that leaves the receiving corps searching for his successor.
While the Red Wolves will probably do almost as well in the win-loss column, some of their offensive stats will suffer from his departure.
McKissic will take the biggest hit, because he's the leading receiver. He'll still be the leading receiver, but not with as many yards.
Stat line from 2012: 103 receptions for 1,022 yards and five touchdowns.
Eric Ward and the rest of the Texas Tech Red Raiders will play without quarterback Seth Doege next season. Doege is one of many Big 12 senior quarterbacks leaving programs, including Landry Jones and Collin Klein to pick out a couple of other big names.
Doege will not be orchestrating any more 56-53 triple-overtime thrillers for the Red Raiders, and Ward's stats will show that. The only plus for Ward is that his biggest competitor, Darrin Moore, will also be leaving.
That will help offset the loss of yards a bit, but it will still be difficult for Ward to match his 1,000-plus-yard 2012 performance next season.
Stat line from 2012: 82 receptions for 1,053 yards and 12 touchdowns.
Zurlon Tipton was Central Michigan's leading rusher in 2012, and the Chippewas capped the season off with a heart-stopping win over the Western Kentucky Hilltoppers in the Little Caesars Bowl.
Tipton had the luxury of running behind one of the best blockers in the nation. Unfortunately for Tipton, Eric Fisher will be picked up by the NFL this April. He'll probably go in the first round, and that will leave a massive wound in the offensive line.
As Tipton figures out how to take advantage of what opportunities he has during each game, Fisher's absence will be felt intensely. Tipton will not approach the 1,500-yard mark in 2013 like he did in 2012.
Stat line from 2012: 252 carries for 1,492 yards and 19 touchdowns.
Central Michigan's leading wide receiver, Titus Davis, won't be pining for just his first-round offensive lineman, he'll be wishing that quarterback Ryan Radcliff hadn't left the program either.
Radcliff will leave a giant hole for the Chippewas, and Davis will bear the brunt of the missing tandem of Eric Fisher and Radcliff. With less protection for a new quarterback, Davis's numbers will fall short of his 800-plus-yards gained in 2012.
Stat line from 2012: 43 receptions for 860 yards and eight touchdowns.
Jamison Crowder played on the hallmark Duke team that went to the postseason for the first time in nearly 20 years. The Blue Devils have plenty of things working against them in 2013, though, and a trip to a bowl is less likely than before.
Sean Renfree, Duke's quarterback, will be leaving this summer, and his absence will be obvious in 2013. Duke will probably not make the postseason, and Crowder's numbers certainly won't be as flashy.
Since Conner Vernon, Duke's other big-time wide receiver, will also be leaving, Crowder will be the top target for opposing defenses to hone in on. If Crowder doesn't figure out how beat other teams' top cornerbacks, then his numbers will fall even further than expected.
Stat line from 2012: 76 receptions for 1,074 yards and eight touchdowns.
Vanderbilt began a rise toward the top of the SEC a couple of years ago, but things are going to take a little step backward in 2013. Not only is running back Zac Stacy leaving, but quarterback Jordan Rodgers is taking off as well. He's expected to go in the sixth or seventh round of the draft.
While that may be welcome news for the next tailback in line, that's bad news for the team's leading receiver. That man is Jordan Matthews, and he will not be thrilled with his stat line at the end of the season.
With the experienced Rodgers gone, the new kid will be expected to step up. Unfortunately, he will not have the respect-commanding Stacy to use as a shield against the pass rush.
That will put the passing game on a precarious perch of perfect timing and brilliant play-calling. Without either, the Commodores are going to have a rebuilding year to forget.
Stat line from 2012: 94 receptions for 1,323 yards and eight touchdowns.
Ka'Deem Carey had such an amazing season in 2012 that it's intuitive that his name appears on this list. How can a tailback do what he did in the first place, much less repeat the performance the next year?
Carey will be helping shield a new quarterback, since the 2012 starter will be gone (more on him in the next slide). As Carey will be attempting more rushes, opposing teams are going to zero in on him and force the first-year starter to beat them with his arm.
Maybe that will happen, and maybe it won't. No matter what happens in the passing game, Carey's numbers from 2012 will live forever as his single-season high in college.
Stat line from 2012: 303 carries for 1,929 yards and 23 touchdowns.
Austin Hill's numbers won't be indirectly affected by the departure of quarterback Matt Scott, they will be directly affected. Scott was the source of Hill's stats, and there will be a first-year starter in his place under center. Scott is a projected fifth-round selection.
While losing a quarterback is difficult enough, losing one that's actually going to get a shot at the NFL is even harder. Hill will have to overcome that major obstacle in 2013, and his stats will suffer.
Regardless of what Arizona does or doesn't accomplish, Hill and Ka'Deem Carey will have to be integrated into a complete offense as opposed to isolated as the complete offense.
Stat line from 2012: 81 receptions for 1,364 yards and 11 touchdowns.
Allen Robinson may get rescued from this scenario by a lightning-fast learner that steps up in Matt McGloin's place under center. Matt Stankiewitch's departure to the NFL will certainly throw a monkey wrench into the plan, though.
Robinson is missing an NFL-quality offensive lineman and an NFL-quality quarterback. That's a seriously difficult situation to overcome. Penn State will still finish in the top half of the Big Ten, but it won't be without overcoming a serious learning curve.
Robinson has the talent to match his numbers from 2012, but he doesn't have the supporting cast to repeat the feat.
Stat line from 2012: 77 receptions for 1,018 yards and 11 touchdowns.
Marqise Lee had a stellar season despite Robert Woods being on the field with him most of the time. Lee outproduced Woods almost 2-to-1 in yardage, and Woods is entering the draft in April.
So, if all the evidence points to Lee's numbers rising, why is he on the list?
For starters, USC's 2012 starting quarterback is ranked second at his position heading into the draft.
If you thought replacing an NFL-caliber quarterback was an impossible task, just imagine replacing a first-round quarterback.
Matt Barkley isn't going to be replaced easily, and USC's Sun Bowl performance at the end of the 2012 season made that quite evident. Lee's numbers will suffer because Max Wittek is no Matt Barkley.
If that weren't bad enough, the Trojans will be missing fourth-round center Khaled Holmes after this spring. They will be breaking in a new quarterback with a new center.
Stat line from 2012: 118 receptions for 1,721 yards and 14 touchdowns.
Syracuse closed the season on a snow-bowl win over the West Virginia Mountaineers. It was a big win for the Orange, but it was also Justin Pugh's last game in the Orange uniform.
Pugh, an offensive guard, is expected to be scarfed up in Round 3. That will leave Syracuse with a hole to fill on the line. On top of that, quarterback Ryan Nassib is the fifth-ranked quarterback in the draft.
Syracuse is losing some serious talent to the NFL, and Jerome Smith will be expected to carry the load. Unfortunately, that's just not fair to ask of any one player, even Smith.
Smith will assist Syracuse as best he can, and the Orange are definitely not out of contention for a bowl. However, to expect his stats to remain the same or get better is just setting yourself up for disappointment.
With the loss of two NFL-quality players on offense, expect Smith to see a dip in his 2013 stats.
Stat line from 2012: 227 carries for 1,171 yards and three touchdowns.
Kenneth Dixon is up against one of the most daunting sets of circumstances in college football next season.
Not only is he missing three players directly associated with his success, but they are also likely to be signed with NFL squads.
Offensive linemen Jordan Mills (likely third-round pick) and Oscar Johnson (likely seventh-round pick or free agent) are both leaving, and quarterback Colby Cameron is also joining Johnson in the seventh round or free-agent pool.
That leaves Dixon as one of the only major contributors left from last year's highest scoring offense in the nation. Dixon will have his work cut out for him, and he'll have every linebacker on the other side of scrimmage aiming for him.
He won't be running for almost 1,200 yards in 2013.
Stat line from 2012: 200 carries for 1,194 yards and 27 touchdowns.
Amari Cooper is one of the rare breed of players who can contribute heavily as a freshman for the reigning national champions. Not only did he contribute, but he finished as the leading receiver on the squad that earned the first repeat in the BCS era.
Cooper is up against a fiercely talented set of recruiting classes from 2012 and 2013, and every one of those recruits will be trying to do what he did. Overall, this is good for Alabama, but all that competition is bad for Cooper's stats.
Cooper may still finish as the Tide's leading receiver, but with all the offensive line talent that's leaving, another season like 2012 is not likely.
Stat line from 2012: 59 receptions for 1,000 yards and 11 touchdowns.
Along with Amari Cooper, AJ McCarron will join the Tide's list of less-effective players in 2013. It's not his skill level that will hurt him; he will return more skilled than ever in 2013.
What's going to hurt him is losing two first-round draft picks during the offseason and a second-round pick, all from the offensive line. Chance Warmack, D.J. Fluker and Barrett Jones are all leaving The Capstone this spring.
Warmack and Jones are both ranked No. 1 at their respective positions, and Fluker is ranked No. 4 at his. With 60 percent of their starting offensive line gone, McCarron's numbers will undoubtedly be affected.
Sure, he may still find a way to win his third-straight national championship, but his numbers will not be the same.
He finished the season as the nation's leader in quarterback rating, and that was largely due to his protection in the pocket. With that protection gone, he will be sacked more often and forced to throw under pressure.
McCarron's ceiling may be sky-high, but the walls could come crashing in. This is especially true if the new starters don't figure out what to do by the time Alabama plays Texas A&M. That game is on the schedule in Week 3.
Stat line from 2012: 211-of-314 for 2,933 yards, 30 touchdowns and three interceptions with a QBR of 175.3.
Johnny Manziel will have a couple of major disadvantages in 2013 compared to 2012. He's missing the best offensive lineman in the country, Luke Joeckel, and he has given the SEC an entire year of game tape to review before they play him a second time.
This doesn't mean that Texas A&M isn't in the running for the SEC title game next season, but it does mean that his numbers will not likely be as high. He can afford to drop some yardage in both the passing and running games and still make a run at the national title, though.
Manziel and the Aggies can certainly afford to drop some points and yards from certain games, but they will have to have stellar showings against LSU, Alabama and whoever they meet in the SEC title game.
Stat line from 2012: 295-of-434 for 3,706 yards, 26 touchdowns and nine interceptions. He also had 201 carries for 1,410 yards and 21 touchdowns.