Every year in the NFL, a bunch of great players fall off a cliff. These nosedives can be attributed to the aging process, injuries, personnel changes or simple bad luck. Here’s our pathetic attempt to predict who might fall off the face of the superstar planet in 2011:

1. Peyton Manning, Indianapolis Colts

Tomlinson’s take: When and if he plays, it could be like watching the Michelin man take snaps. As long the offense is drawn up so that his receivers are directly in front of him and minimal neck movement is required, Manning should be just fine.

Gagnon’s take: And if he doesn’t play, the Colts will suck. Either way, our expectations are very low.

2. Eli Manning, New York Giants

Tomlinson’s take: From a fantasy standpoint Peyton’s little brother should still post serviceable numbers. But in the world of reality where winning games is all that matters, watching the Giants’ offense could be on par with being conscious during an appendectomy.

Gagnon’s take: That was really random, Sean. Too many losses on both sides of the ball in New York. Eli will have another tough year.

3. James Harrison, Pittsburgh Steelers

Gagnon’s take: The 2008 defensive player of the year is 33 years old and out of shape after undergoing dual back surgeries in the offseason. His time at the top was short and sweet, and it’s over.

Tomlinson’s take: In addition to Father Time beginning to be a jerk, life will continue to be tough as a highly physical and borderline hostile player adjusts to a league that’s increasingly discouraging barbaric behavior.

4. Jared Allen, Minnesota Vikings

Gagnon’s take: Allen’s only 29, but you have to wonder if he’s fading from his prime as the Vikings’ defense (and Allen’s support system) gets older. It won’t help that his top complement, Ray Edwards, left as a free agent.

Tomlinson’s take: Whether it’s led by McNabb or later rookie Christian Ponder, the Vikings offense’ could put the defense in low leverage situations, possibly making Allen’s prime sack opportunities scarce.

5. Frank Gore, San Francisco 49ers

Gagnon’s take: The 28-year-old has the knees of a 68-year-old. It couldn’t be more obvious that the injury-prone Gore is about to hit a wall.

Tomlinson’s take: Age and brittleness are a lethal combination. Gore has played in a full 16-game season just once in his career, missing nine games over the last three years.

6. Reggie Wayne, Indianapolis Colts

Tomlinson’s take: I like Kerry Collins as a hopefully temporary Manning replacement, but I’d like him a lot more if it was 2002, 2005, or even 2008.

Gagnon’s take: Notwithstanding the Manning situation, Wayne isn’t a spring chicken either. He’ll turn 33 this season — maybe the decline would start regardless.

7. DeAngelo Williams, Carolina Panthers

Gagnon’s take: We haven’t been shy to criticize Williams and his monster contract. Jonathan Stewart and Mike Goodson might be better options in a bad offense. It’s hard to envision the 28-year-old Williams coming close to 16 starts in 2011.

Tomlinson’s take: Seeking to match Gore’s glass imitation, Williams has missed 13 games over the past two seasons. His feeble ways will only increase when he’s asked to shoulder a larger load while the Panthers’ backfield supports rookie quarterback Cam Newton.

8. Jason Babin, Philadelphia Eagles

Gagnon’s take: He was in the right place at the right time when he registered 12.5 sacks in 2010. In 2011, he joins a Philly defense that has several better pass-rushing options. And even if he does get plenty of opportunities to rush the quarterback, it’s possible his 2010 campaign was an anomaly.

Tomlinson’s take: Opposing offenses may quickly learn to exploit a weak linebacker corps after the departure of Stewart Bradley, which is the only glaring weak area for the Philadelphia defense on paper. Faced with a barrage of runs and screens to keep him honest, Babin’s sack numbers could take a sharp decline.

9. Steven Jackson, St. Louis Rams

Gagnon’s take: Here’s yet another 28-year-old running back who is about to fall off the cliff. He started the stumble toward the edge last year with an abysmal 3.8 yards per carry.

Tomlinson’s take: The motivation to bring in Cadillac Williams is clear, and he’ll quickly form a platoon with Jackson. Jerious Norwood’s explosive speed will also be utilized on screens and pass routes out of the backfield, providing the Rams with another insurance option against Jackson’s age.

10. Percy Harvin, Minnesota Vikings

Tomlinson’s take: I throw a better spiral than Donovan McNabb, and in high school I was once sacked for a safety, only to get up and learn I was on an entirely different field than where the game originally started.

Gagnon’s take: And you weren’t even the quarterback…

11. Brandon Lloyd, Denver Broncos

Gagnon’s take: He might not be considered elite by most observers, but his numbers were elite in 2010. Was that a fluke? While it’s promising that Kyle Orton will continue to throw him passes, I think Lloyd’s stats will decrease considerably this year. John Fox will want to run the ball a lot more, just as he did in Carolina.

Tomlinson’s take: Demaryius Thomas, the Broncos’ first-round pick in 2009, will return early in the season after he tore his Achilles tendon during a workout in February. He had 22 catches for 283 yards–including a 97-yard performance in Week 2–while playing in just 10 games last year, and he’ll be ready to steal looks from Lloyd.