In a violent sport like football, injuries are as much a part of the game as checkdowns and off-tackle runs.
From star quarterbacks to young safeties, no player is safe from the injury bug, and some players need more time than others to recover.
The following players suffered brutal injuries in 2011 and need to be monitored throughout training camp.
Peyton Manning missed all of 2011 with a neck injury, but the star quarterback is attempting to make a comeback with the Denver Broncos.
Manning isn't yet 100 percent healthy, and he isn't inspiring much confidence by dinking and dunking his way down the field in practices.
However, even a slightly healthy No. 18 is a passing upgrade over Tim Tebow in Denver, so Bronco fans should be excited.
Matt Schaub has hit the ground running at Texans camp and is ready to lead his team to the Super Bowl.
After undergoing Lisfranc surgery in 2011, Schaub is back in pads and practicing at full speed with a strong 2012 in mind.
Look for this player to shake off his injury and go back to being the franchise quarterback that the Texans know him to be.
A situation worth monitoring, the status of Adrian Peterson's ACL injury is still rather iffy and should clear up as training camp goes on.
This running back can be a star when he's firing on all cylinders, but just be mindful of the fact that torn ACLs are very difficult to bounce back from.
Though he's also coming off a grisly ACL injury, Jamaal Charles looks to be 100 percent back and ready to perform.
Indications out of Chiefs camp are strong that the running back is ready to carry the ball again, with Charles himself even proclaiming that he has his "mojo" back.
For those fantasy football owners out there, be aware that Charles will be splitting carries (h/t Rotoworld) with new Chief Peyton Hillis.
Mario Williams did suffer a torn pectoral muscle in 2011, but he's fully recovered and has been dominant in Buffalo Bills camp.
Unsurprisingly, Williams has been extremely explosive and has been making big-time plays in practice according to Bleacher Report's own Chris Trapasso.
Look for this defensive end to have a monster season in 2012.
After a torn ACL, many figured that Eric Berry would be unable to make a big return for the 2012 season. These doubters, thus far, have been wrong.
Berry has been a true beast in practices so far, and he wants to do even better, which is admirable.
This safety should be able to lead the Chiefs' defensive backfield, as he is now fully recovered.
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