NFL Fantasy 2012: Highlighting This Season's Riskiest Superstars

Just because a player is considered a superstar, it does not guarantee anything in fantasy football.

In real football, winning games is the only thing that truly matters to the players and coaches. Peyton Manning is a prime example of that because, despite the numbers he's put up throughout his career, winning is really all he cares about.

As for fantasy football, Manning is a risk in 2012, but he's not the only superstar to be concerned with. Now, it's not that these players aren't worth drafting, but just be aware of the potential that exists for them to have a down year this season.

So, let's get to it and check out the riskiest fantasy-football superstars in 2012.

Chris Johnson: RB, Tennessee Titans

It was not surprising to see Chris Johnson have a disappointing season in 2011 after holding out.

Still, the man did manage to gain over 1,000 rushing yards and Johnson also added 418 receiving yards. Unfortunately, Johnson only scored four touchdowns, fumbled three times and averaged just four yards per carry.

Looking at 2012, and we can expect Johnson to have a better year, but another frustrating performance is quite realistic instead. This season, a rough year for Johnson will be courtesy of a schedule featuring many top defenses.

The Tennessee Titans already have four games versus the Houston Texans and Jacksonville Jaguars, as both are AFC South division rivals. In addition, Tennessee gets to face the Pittsburgh Steelers, New England Patriots, Buffalo Bills and New York Jets.

Those teams are solid against the run, and you can also expect Johnson's number of carries to be restricted when facing explosive opponents like Green Bay, Chicago and Detroit.

The Titans will be in high-scoring affairs in those contests, and Tennessee's defense isn't good enough to consistently slow opponents down. Provided that the passing game improves, Johnson won't have defenses stacking the box against him as much, but he is still the focal point of Tennessee's offense.

Vernon Davis: TE, San Francisco 49ers

Vernon Davis is part of a significantly bolstered offense, but at the same time, that will affect his fantasy-football production.

He may be Alex Smith's favorite target, but San Francisco has plenty of other targets to consider as well. Receivers like Randy Moss and Mario Manningham will certainly help the development of Michael Crabtree, not to mention take a significant amount of pressure off the running game.

We have to keep in mind that the 49ers are still a run-oriented offense, but now with a more threatening passing game. Let's not forget about ground-game additions Brandon Jacobs and rookie LaMichael James, who can help Frank Gore.

In 2012, Davis will make great improvements as a blocking tight end and become a more efficient receiver. He may not haul in as many receptions as 2011, but Davis will gain many yards after the catch because he'll see a lot of single coverage.

San Francisco's schedule is not overly difficult, either. So with the talent to go up early in many games, the Niners will be running the rock even more in the second half.

Jamaal Charles: RB, Kansas City Chiefs

After missing basically the entire 2011 season due to injury, Jamaal Charles is a fantasy risk from that perspective alone in 2012.

Another reason why Charles is a risk this season is due to the possible holdout of receiver Dwayne Bowe. Now, a holdout would be surprising nonetheless, but even if Bowe shows up for training camp, we cannot expect a performance like he displayed in 2010 and 2011.

For one, he'll see a constant double-team, and the rest of the defense will zero in on shutting down Charles. And what if Bowe does hold out?

Well, that would only make life tougher for Charles and the Kansas City rushing attack. Matt Cassel is a solid quarterback, but without any true No. 1 receiver to target (like Bowe) the passing game would suffer.

In turn, that puts more pressure on Charles to perform against a constantly stacked box. Whether it's linebacker spies, run blitzes or man coverage from defensive backs when he's trying to release on a route, Charles will become the sole point of attack for a defense.

On top of all that, a rusty start should just be a foregone conclusion after missing all that time while rehabbing.

Marques Colston: WR, New Orleans Saints

Everything with Marques Colston revolves around what happens with Drew Brees.

According to ESPN, via Mike and Mike in the Morning, Brees is optimistic about getting a deal done. Still, a deal has to get done in order for Colston to ensure a much more productive season than what could happen without Brees.

Last season, Colston was the Saints' second-leading target, with 1,143 yards on 80 receptions and eight touchdowns. Tight end Jimmy Graham led the way, but Colston averaged more yards per catch (14.3).

Having Brees under center does solidify another strong year for Colston. However, New Orleans does remain in dire straits after the "Bountygate" scandal. That said, don't expect the Saints to be as explosive in 2012 as they were in 2011, even if Brees does get under center.

New Orleans has a much more difficult schedule this season, and the defense is still a work in progress. Opponents like Green Bay, San Francisco, the entire NFC East and the entire NFC South will be bringing pressure on every down, no matter who is at the helm.

And if Brees ends up holding out, well, just scratch off Colston all together because the man has only caught passes from the NFL record-holder from day one.

The New Orleans offense will go as Drew Brees goes, and without him, Marques Colston's fantasy value takes a nosedive.

Peyton Manning: QB, Denver Broncos

Yes it's Peyton Manning, and the man may have four NFL MVP awards, but he also has had four neck surgeries.

Not having played since the 2010 season, Manning is 36 years old and, to some extent, is starting his career over with the Denver Broncos. There's no doubt that Manning can still be a productive quarterback and legitimately lead the Broncos in the immediate future.

However, having sat out an entire season and with health flags, it's hard to believe that Manning will fully return to his pre-2011 self. For Denver's sake, let's hope he does, but it's not like the Broncos offer much in the passing game, either.

Demaryius Thomas is still a developing player and Eric Decker needs to add more production to his efficiency.

Fortunately, Denver does have Jacob Tamme at tight end, but even he still has much proving to do as well. Manning will certainly enhance each of these players' skill levels, so it's not like a horrific season will happen.

We just have to be realistic about Manning's return and how the Broncos' offense orchestrates as well. In 2011, Denver ranked No. 1 in rushing, and aside from Tim Tebow, veteran Willis McGahee proved he can still do some solid work.

Add in rookie Ronnie Hillman this season and Denver will be a balanced offense to take pressure off Manning.

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