In 2011, several NFL players had surprising breakout seasons that catapulted them to stardom. But in the NFL, things can change in an instant, and one great season doesn't ensure long-term success.
The following is a list of players who must repeat their stellar performances if they hope to help their teams win in 2012.
Victor Cruz exploded onto the scene in 2011 with a remarkable individual season that helped lead his New York Giants to a Super Bowl win.
Cruz finished the year with 82 catches for 1,535 yards and nine touchdowns. In the process, he became one of the NFL's premier deep threats.
If the Giants hope to repeat as Super Bowl champions, Cruz is going to have to find a way to be just as explosive in 2012. Fellow receiver Mario Manningham has taken his talents out west to the San Francisco 49ers, which means Cruz will be counted on even more heavily.
He will need to prove himself as a legitimate top target and show that 2011 wasn't a fluke.
The 25-year-old UMass product has the natural ability to get the job done; the key will be keeping his focus amid the bright lights and attention of playing in New York.
If he can post similar numbers this year, the Giants have to be considered the favorites in the NFC East.
Calling Arian Foster a "breakout star" for his 2011 performance might be a stretch, since he led the NFL in rushing in 2010.
But I think Foster legitimized his out-of-nowhere season from 2010 by posting great numbers in 2011 and leading the Houston Texans to their franchise's first playoff berth.
If the Texans want to remain atop the AFC South, Foster will need to continue his dominance of opposing defenses in 2012 and stay healthy for the entire season.
In 13 games in 2011, Foster rushed for 1,224 yards and 10 touchdowns, while also catching 53 passes for 617 yards and two more scores.
The 25-year-old will obviously be the key to Houston's offense again this season. Foster will need to produce, especially with quarterback Matt Schaub working his way back from a season-ending foot injury.
San Diego Chargers running back Ryan Mathews finally got rolling midway through the 2011 season. The Fresno State star finished the year with 1,091 yards and six touchdowns on 222 carries (4.9 yards per carry). He also caught 50 passes for 455 yards.
When Mathews got himself going, it took a ton of pressure off quarterback Philip Rivers, who had a subpar season thanks to near-constant pressure from opposing pass rushes.
In 2012, Mathews will have to continue his development if the Chargers want to find a way back into the playoff hunt.
Mathews has had issues staying healthy and holding onto the football. In his third season, those need to become a thing of the past. With fellow running back Mike Tolbert now plying his trade with the Carolina Panthers, Mathews will be leaned on full-time.
In 2012, Mathews must show that he is a legitimate No. 1 back and prove that the development we saw at the end of last season wasn't a fluke.
I'll admit it: I was wrong about Cam Newton.
Everyone knew he had the talent to do big things in the NFL, but I didn't think he would be able to make a smooth transition to professional football.
In 2011, Newton had one of the finest rookie seasons in NFL history. He completed 60 percent of his passes for 4,051 yards, with 21 touchdowns and 17 interceptions.
While his quarterback rating was a pedestrian 84.5, he also rushed for 706 yards and 14 touchdowns. He was easily the AP's Offensive Rookie of the Year and also reached the Pro Bowl.
The problem for Newton is his supporting cast. He didn't have a whole lot of help in 2011, and as a result, his Carolina Panthers finished 6-10.
If the Panthers are to compete in the NFC South this year, Newton will need to come close to replicating his success from last season.
He'll be counted on to dominate opposing defenses yet again, and if he can't do it, Carolina will be making another top-10 selection in the 2013 NFL draft.
The Denver Broncos made big headlines this offseason by signing free-agent quarterback Peyton Manning. But what got lost in all the discussion about adding the four-time MVP is that Denver's defense still had a lot of work to do to get better.
In 2011, Von Miller exploded as a rookie, racking up 64 tackles, 11.5 sacks and two forced fumbles en route to being named AP's NFL Defensive Rookie of the Year.
The 245-pound linebacker was a terror for opposing defenses and helped spark a Denver defense that desperately needed it.
Entering this season, it appears Miller will have to repeat his success from last season if the Broncos are going to repeat as AFC West champions. The team didn't add much defensively, instead focusing its attention on bringing Manning into the fold.
Miller will have to prove his success in 2011 wasn't a fluke and that he can continue to provide that kind of spark defensively.