Plenty of starting positions will be up for grabs in NFL training camps this summer, but it's the quarterback battles that are always certain to attract the most attention.
Arguably as many as eight teams are without a definitive starter at the game's most critical position. Let's examine those eight squads and attempt to determine who will open the season under center for them.
BUFFALO BILLS: KEVIN KOLB vs. E.J. MANUEL
New Bills coach Doug Marrone and the front office made a bold move in drafting Manuel, thought to have an enormously high ceiling but viewed as a raw project, in the first round. Since the draft, however, Manuel has said that the Bills offense has been easier to learn than Florida State's, and new general manager Doug Whaley said he is open to Manuel being the Day 1 starter.
Prior to the draft, the Bills had signed former Arizona Cardinals and Philadelphia Eagles quarterback Kevin Kolb, who has enjoyed some encouraging moments in the NFL during the occasional times he hasn't been injured. There is little question Kolb is more polished, but will the Bills be able to resist the temptation to turn the keys over to their prized draft pick?
This one could go down to the wire. If Manuel progresses quickly, the Bills would probably like to start him. If he experiences major growing pains (the more likely scenario), he could end up being the backup for, say, half the season before eventually assuming the job.
It's tough to predict how ready Manuel will be because we're two and a half months away from his first game action. Let's say it's roughly 60-40 in Kolb's favor to start on opening day, but that figure has the potential to change in a hurry when the preseason games begin.
CLEVELAND BROWNS: BRANDON WEEDEN vs. JASON CAMPBELL vs. BRIAN HOYER
The Browns' new coaching staff seemed to be lukewarm on incumbent starter Weeden at first, but the team ignored the quarterback position in the draft. Instead, Cleveland signed a pair of solid backups in Campbell and Hoyer, with the idea they will push the 2012 first-round draft pick.
Weeden is not a lock to open the season behind center, but it would be a fairly big upset if he doesn't. The presence of the other two guys, however, gives Cleveland one of the best backup quarterbacks in the league and probably the finest No. 3. The new staff and front office aren't married to Weeden, so he won't keep the job for long if he doesn't perform.
One thing working against Weeden is his age. Despite entering just his second NFL season, the former New York Yankees farmhand is going to turn 30 in October. Coach Rob Chudzinski and general manager Mike Lombardi are not going to be as patient with Weeden as they would be with the typical second-year quarterback.
Still, Weeden seems to be a decent fit for Chudzinski and offensive coordinator Norv Turner's vertical attack, and that would give him a decent chance to hang onto the job for a while.
JACKSONVILLE JAGUARS: BLAINE GABBERT vs. CHAD HENNE
Had the Jaguars not changed coaching staffs (or their general manager) this offseason, Henne might have had a leg up in this battle. Judging them by the eye test last year, Henne seemed to give Jacksonville a slightly higher quality of play than Gabbert.
The guess here is that Gabbert, unless he is particularly putrid during the preseason, will emerge as the opening day starter. The franchise spent a No. 10 overall pick on him just two years ago, and he's still only 23. The new regime is going to want to give him one last chance to succeed based on that investment.
Jacksonville signed Henne as a free agent last year, after the Miami Dolphins declined to offer him a contract. The Jags' investment in him was not nearly so great.
On the flip side, it's easy to forget that Henne is just 27. He should theoretically be entering his prime. If he should outperform Gabbert considerably in the preseason, it's certainly possible he will land the job.
Basically, though, Jacksonville would want to be positively sure that Gabbert is a lost cause before deciding to cut him loose. The new coaching staff needs to give him another opportunity in order to evaluate him properly. That's not to say he'll have a long leash, though, and it's likely Jacksonville will address the position either early in the 2014 draft or through free agency.
MINNESOTA VIKINGS: CHRISTIAN PONDER vs. MATT CASSEL
It sounds like Minnesota has no real plans to let Cassel challenge for the starting job, so there's probably nothing to see here right now. Ponder, the No. 12 pick in the 2011 draft, took a small step forward last season, helping the Vikings get to the playoffs. He probably deserves the chance to build on his modest success.
However, the presence of Cassel gives Minnesota a more viable backup option. Joe Webb, who has since moved to wide receiver, was the No. 2 quarterback last year, and there's almost no chance the Vikings' coaching staff viewed him as a potential long-term answer as a signal-caller.
If Ponder doesn't continue to improve this season, Minnesota would be less reluctant to pull the plug now. Perhaps the competition from Cassel, perceived or real, will bring out the best in Ponder.
It's almost 100 percent certain Ponder will be the opening day starter. He'll need to play well to close the season with the job, though.
NEW YORK JETS: MARK SANCHEZ vs. GENO SMITH
The Jets surely wish it would have never come to this. Incumbent quarterback Sanchez is entering his fifth season and is only 26. He led the Jets to a combined four playoff wins (the franchise career record) in the 2009 and 2010 seasons, but those victories seem a distant memory now.
Starting 31 games over the past two seasons, Sanchez has been personally responsible for a staggering 52 turnovers during that time. With still one of the better defensive units in the game, the Jets could probably be competitive by merely avoiding so many mistakes at the quarterback position.
So, the question is, can Smith be the guy to deliver mistake-free performances as a somewhat raw rookie? He'd have to make the shift to a West Coast offense, and he'd have to get used to taking a good percentage of his snaps from under center after having operated almost exclusively out of the shotgun at West Virginia.
Throwing Smith to the wolves (and Tampa Bay Buccaneers) on opening day would not appear to be the ideal situation, but the guess here is that it will happen. Sanchez's veteran teammates seem to have lost confidence in him and, worse yet, his self-confidence has appeared to completely vanish. Turning the job over to Smith might be necessary to re-energize the organization, but it's hard to say what effect it would have on coach Rex Ryan's job security.
OAKLAND RAIDERS: MATT FLYNN vs. TERRELLE PRYOR vs. TYLER WILSON
Could Flynn go from projected starter to clipboard holder during his second consecutive preseason? The Seattle Seahawks signed him as a free agent in 2012, presumably to take over as their starter. Late in the exhibition schedule, however, third-round rookie Russell Wilson overtook him and guided Seattle to the playoffs.
Prior to this year's draft, Oakland traded for Flynn. Then the Raiders drafted Arkansas' Wilson in the fourth round. He made a big impression at his first rookie mini-camp, which is what initiated the talk that he could seriously challenge for the starting job.
An entirely different regime was responsible for drafting Pryor and he does not appear to be a fit for what the Raiders want to do offensively. He could be an effective option to run the Wildcat, but he would seem the least likely of the three candidates to earn the starting nod.
The bottom line is that this is a rebuilding team, thanks in large part to all its dead money against the salary cap. With no pressure really to win immediately, the Raiders might opt to turn the offense over to their likely quarterback of the future, Wilson, who was thought to be one of the most pro- ready passers available in the draft.
Flynn will enter the preseason as the No. 1 guy, so he surely has a chance to win the job. He'll have to be really good in order to do it, though. We're going to go with a mild upset here and predict Wilson takes the job and runs with it.
PHILADELPHIA EAGLES: MICHAEL VICK vs. NICK FOLES vs. MATT BARKLEY
New head coach Chip Kelly is a real wild card. No one knows for sure how much his offense with the Eagles will mirror the attack he implemented at the University of Oregon.
Vick has restructured his contract, which will now pay him at least $7.5 million for the 2013 season, then allow him to become a free agent. It seems logical that he will be the starter for much of this season, while Barkley, the only quarterback Kelly has hand-picked, is groomed to take over by 2014.
Then again, how similar could Kelly's Oregon and Eagles offenses be? With his mobility, Vick would appear to be a decent fit. The same can't really be said for Foles or Barkley, but Kelly wouldn't have traded up to draft Barkley in the fourth round if he didn't think the former Southern Cal quarterback could run his offense.
Because of the financial commitment and the fact that Vick looks like the best fit for the offense right now, he remains the clear favorite to open as the starter. Gradually, Kelly's offense will probably evolve into one that plays more to Barkley's strengths. The rookie could be the starter by the end of this season.
TAMPA BAY BUCCANEERS: JOSH FREEMAN vs. MIKE GLENNON
At first glance, it looked like Tampa Bay was really just drafting a developmental quarterback with a high ceiling to learn while playing behind Freeman. Buccaneers head coach Greg Schiano, however, has gone out of his way to get the word out that Glennon has a realistic chance earn the starting job.
Pre-draft reports had surfaced out of Tampa Bay that Schiano was not really sold on Freeman as the franchise quarterback, even though the team's front office apparently did not share that opinion. The team drafted Glennon in the third round, so it's not likely the Bucs view him merely as a long-term backup.
When they poured so much money into rebuilding their secondary by trading for Darrelle Revis and signing free agent Dashon Goldson, the Bucs made it clear they believed they were in a win-now mode. Even if Schiano would ultimately like to see Glennon earn the starting nod, it's unlikely that a win-now team would give him the job as a rookie. After all, for any faults that Schiano sees with Freeman, the fifth-year pro did throw for over 4,000 yards and 27 touchdowns last season.
So Freeman is the heavy favorite to open as the Bucs' quarterback, but things could really get interesting in 2014. Freeman is entering the final year of a rookie contract that will pay him $8.43 million this fall. If Tampa Bay lets him get to free agency, Freeman would probably command twice that much annually on the open market; he'd only be 26 years old with five years of starting experience heading into 2014.
Will Tampa Bay be willing to tie up around $32 million (or about 25 percent) of its cap space on just Freeman and Revis? The Bucs probably won't, as long as they're comfortable with Glennon.