Protecting the quarterback is one of the single most important objectives in football. It's the reason five of the biggest players on every roster comprise the offensive line and explains why tackles are some of the highest paid players in the league. As we head into the 2008 season, it seems most teams have done a great job ensuring their quarterbacks are healthy.

While several guys have some bumps and bruises, questionable injury histories, or have been recovering from offseason operations, quarterback is a relatively healthy position across the league. In fact, almost all of the top QB options come with almost no injury concerns. Most the injuries you'll want to keep an eye on involve younger quarterbacks looking at possible breakout years or former stars looking to recapture past production. Here's a look at the most pressing quarterback injuries across the league:

Sixteen starts. 30 TDs. You don't even need to pencil those numbers in. You can engrave them if you like. Give or take a few TD passes, that's what your getting from the Colts Peyton Manning. I wrote those words on July 13. The next day, Manning, who has missed just one play in his career due to injury, underwent surgery to remove an infected bursa sac in his left knee. We're already about three weeks into a 4-6 week recovery period for Manning, which, at worst, would put him back two weeks before the Colts' regular-season opener. Since removing the bursa did not involve entering the knee joint, it's unlikely there would be any long term ramification physically. In the short term, you'll have the inevitable questions about Manning, his readiness, and the timing of the offense.

Honestly, though, is there any other quarterback in the league who prepares the way Manning does? Maybe, and it's a big maybe, Manning is a bit rusty early, but the Colts have a bye in Week 4, so expect Manning to be just fine from that point on. Marvin Harrison hasn't missed a beat early in camp, even if you think of anything he does this year as gravy. Reggie Wayne has emerged as one of the best three or four receivers in the NFL, Dallas Clark is coming off a career year, Anthony Gonzalez will only get better in his second year, and the running game remains one of the best in the league. Sixteen starts and 30 TDs still looks like a very safe bet for Manning.

Outside of Manning, there are almost no injury concerns with the upper tier quarterbacks as camps open across the league. Tom Brady, Drew Brees, Tony Romo and Carson Palmer all come without question marks. Brady never misses time, and Brees has missed just one game in four years. Romo dealt with a severely bruised right thumb injury late in the season that contributed to some lackluster games, but it's nothing to worry about now, and Palmer hasn't missed a game due to injury in three years. Plus, his quick recovery from the torn ACL he suffered in the '06 playoffs is well documented.

This brings us to a middle tier group of quarterbacks who come with both health concerns and breakout or rebound expectations. The group starts with the Broncos' Jay Cutler, whom Denver fans hope will finally put the John Elway era to bed. It was revealed in May that Cutler has Type I diabetes, a condition that caused him to lose 35 pounds and often feel incredibly tired last season. Now that Cutler is receiving insulin daily, teammates say they've already noticed a change in the quarterback's energy and focus. It should help his stamina as well. Teammates and opponents saw a noticeable decrease in Cutler's energy levels late in games last season. As long as WR Brandon Marshall can avoid stray McDonalds bags, Culter will have a rising star to work with. In addition, Darrell Jackson is hoping Cutler, who may have the strongest arm in football, will revive his career as a deep ball specialist. If Culter managed 20 TDs and 3,500 yards while dealing with unknown diabetes during his first full season as a starter, the writing is on the wall for much bigger things in '08.

The days of the Rams' Marc Bulger being an elite quarterback are over. He played for two weeks last season with broken ribs before he eventually had to miss two games. He also missed two more games due to a concussion. To be fair to Bulger, his offensive line was decimated by injuries, and having Orlando Pace back should be a big help. Torry Holt dealt with lingering knee injuries, but still played in 16 games and remains an elite WR. A healthy Stephen Jackson caught 90 passes out of the backfield two years ago and will keep defenses honest for Bulger. He'll need it as his body has taken a beating on a hard surface. The near 200 sacks he's suffered (almost three per game) in the last five years have taken a toll. Bulger is a good bet to miss a few games due to injury, so have a solid back-up plan, but he should still provide big numbers at times.

For years with the Falcons, Houston's Matt Schaub was considered the best backup QB in the league. Finally a starter with the Texans last year, Schaub's campaign was derailed by injuries. He left one game with a hip injury and another with a concussion that ultimately cost him two games. The worst injury was a dislocated left (non-throwing) shoulder suffered in Week 13. Schaub missed the rest of the year and had the shoulder surgically repaired in the offseason. Schaub hasn't appeared to have any problems in camp, but there has to be questions about a guy who dealt with so many injuries in his first year as a starter. In the eight fully healthy games Schaub played, he threw nine TDs and averaged 263 yards. Schaub is a risk, so plan accordingly, but he can provide great value if both he and Andre Johnson are healthy.

Is he Carson Palmer or Daunte Culpepper? Those are the comparables when evaluating the Chargers' Philip Rivers. The torn right knee ligaments he played with in the postseason have been repaired and, remarkably, Rivers was running full speed just over four months after the operation. He's been leading the first team offense like normal in Chargers' camp. Be cautious, though, as Rivers' injury involved damage to more areas of the knee than did Palmer's. Rivers is in much better shape (and far more motivated) than Culpepper was, so it's safe to lean toward a recovery closer to, but likely not as smooth as, Palmer's. If healthy, Rivers has more offensive tools than he or Brees have ever had in San Diego. Add massive, but still-improving WR Vincent Jackson and a finally happy Chris Chambers to the dynamic duo of Antonio Gates and LaDainian Tomlinson and the Chargers don't lack for offensive weapons for Rivers.

Assuming Brett Favre has thrown his last pass in Green Bay, that leaves us with Aaron Rodgers. While there's really not enough data at this point to determine Rodgers' durability as a starter, he does come with some injury concerns. Days after his big performance against Dallas last year, Rodgers injured a hamstring in practice that forced him out of action for a few weeks. In '05, while filling in for Favre against New England, Rodgers suffered a broken foot that ended his season. We're not suggesting he's injury-prone, but consider it a warning to tread a bit carefully. There's a lot to like about Rodgers in this offense,with a solid running game and big-time receivers such as Greg Jennings, Donald Driver and James Jones. Rodgers certainly could have a breakout season, but based on one solid game last year (and the team he plays for) Rodgers is likely going to be a bit overhyped.

The Panthers' Jake Delhomme appeared to be on his way to another big season through three games last year, throwing eight TDs and just 1 INT in those games. That's when a gimpy right elbow finally gave way, and Delhomme underwent ligament reconstruction (Tommy John) surgery in mid-October. He didn't begin throwing until February and has slowly progressed through a program that, by all indications, has been successful. Delhomme is practicing with the first team in camp, and both he and his teammates say his arm strength is great. If Delhomme is healthy he'll still have all-world WR Steve Smith to work with in addition to offseason acquisitions D.J. Hackett and Mushin Muhammad. Rookie running back Jonathan Stewart and OT Jeff Otah, both first-round picks, will help the offense as well. Delhomme may be '08's highest risk/reward play.

After showing positives sign at the end of his rookie season in '06, Washington's Jason Campbell was not able to take the next step so many predicted in '07. A dislocated knee cap ended his season after 13 games, but Campbell was average at best in those contests. He threw multiple TDs just three times and had five games without a passing TD. There are several positives changes with Campbell, though. He recovered from the knee injury in a little over a month, and after dealing with a minor hamstring strain in May he's been just fine thus far in Redskins camp. Bringing in Jim Zorn and his West Coast offense, as well as taking two big receivers in the second round of the draft (Devin Thomas and Malcolm Kelly), suggests the Redskins are going to be look for more air deliveries at FedEx Field this season.

Let's wrap up with one of the league's biggest enigmas: Titans QB Vince Young. He was slowed at times last year by a right quad injury that kept him out of one game early in the season. Of course any lingering injuries to Young's legs drop his production and value, so watch for any recurrences. The Titans are hoping for more consistency with the return of Mike Heimerdinger as the offensive coordinator. Young gets the proverbial "safety valve" in TE Alge Crumpler, but even that's not going to be a huge help to what may be the worst receiving corps in the NFL.

The Cardinals' QB situation could provide ample opportunities for either Matt Leinart or Kurt Warner. As long as Leinart's surgically repaired shoulder holds up, he has the potential to break out in his third year throwing to one of the league's best WR duos in Larry Fitzgerald and Anquan Boldin ... Warner is worth keeping an eye on if he takes over for Leinart at some point ... Favre is going to end up somewhere. If it's Green Bay, expect solid numbers but a small decline from last season ... Anywhere else will likely lead to a further decrease in production... With Mike Martz in San Francisco, keep an eye on Alex Smith and Shaun Hill. Bryant Johnson and Isaac Bruce have been added to the receiving corps, and Vernon Davis is a star in the making. Whoever wins that job, with Frank Gore keeping defenses honest, has a chance to put up big numbers under Martz.

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