As we hurtle toward the 2012 regular season, numerous players across the league have something to prove. These guys cover all positions and experience levels, from rookies to seasoned veterans. Some are familiar names and some are completely overlooked, but they all have opportunities to play crucial roles for their respective teams.
Here are two players -- one offensive and one defensive -- with something to prove on each AFC team. Check back on Wednesday for the NFC installment.
Offense: Tandon Doss, wide receiver
Doss doesn't have great speed, but he's a smart guy with great hands who knows how to find the holes in zone coverage. He could fill that crucial third-receiver role for Baltimore, though free-agent signee Jacoby Jones is also an option.
Defense: Paul Kruger, defensive end
Kruger, who is athletic enough to drop into coverage or rush the passer, recorded 5.5 sacks as a backup last season. But he has only started one game in three years. If the Ravens are going to be good on defense, Kruger must step up in the absence of the injured Terrell Suggs and former Raven Jarret Johnson.
Offense: Cordy Glenn, offensive tackle
The Bills desperately need a left tackle. The rookie Glenn is light on his feet and has long arms, great hands, strength and size. They talk about guys who block out the sun, but Glenn (listed at 6-foot-5 and 343 pounds) is big enough to block out the sun and the moon.
Defense: Aaron Williams, cornerback
Williams looks the part of a great corner -- he has the size, speed and athletic ability -- but needs to pick off more passes (he had one interception in nine games last season) and be a little tougher in coverage.
Offense: Andy Dalton, quarterback
Dalton is fairly well-known, but he's absolutely crucial to the Bengals' success on offense. A good leader and smart player, Dalton must improve his arm strength.
Defense: Taylor Mays, safety
Mays, a former second-round draft pick, has good size (6-3, 230) and speed, but lacks instincts at the safety position. Coordinator Mike Zimmer does a great job with players like Mays, who had just 10 tackles in 2011 but already has six this preseason.
Offense: Greg Little, wide receiver
The Browns must boost their passing attack, which averaged 193.1 yards per game last season, 24th in the league. Little, who had a nice 2011 campaign (61 catches for 709 yards and two scores), is still learning the position. He's kind of a big Michael Irvin type; he isn't very fast, but carries the uniform so well that he can run right past defenders.
Defense: John Hughes, defensive tackle
The rookie is probably a two-down player, but he's also big, strong and competitive, and can help fill in for the injured Phil Taylor.
Offense: Willis McGahee, running back
McGahee needs to stay healthy and reproduce the kind of production he had in 2011 (1,199 yards and four touchdowns on 249 carries) if the Broncos want to have a chance in the AFC West. He might be 30, but he looked like a 23-year-old on Saturday, when he scored a touchdown against the Seattle Seahawks in a 30-10 preseason loss.
Defense: Derek Wolfe, defensive lineman
This talented, pass-rushing rookie recorded outstanding times in the three-cone (7.26 seconds) and 20-yard shuttle (4.44 seconds) drills at the NFL Scouting Combine, which usually indicate future success at his position.
Offense: Derek Newton, offensive tackle
Newton doesn't have much experience, having played just two years of major college football (at Arkansas State), but the second-year man has a solid anchor, strong upside and good work habits. I like him to beat out Rashad Butler for Eric Winston's old job.
Defense: Kareem Jackson, cornerback
Starting across from standout Johnathan Joseph, Jackson will be tested in 2012. He's very good against the run, but needs to play better overall. Coordinator Wade Phillips should install some schemes that help maximize his abilities.
Offense: Winston Justice, offensive tackle
Justice is a former second-round draft pick who had an up-and-down six-year career with the Philadelphia Eagles before the Colts traded for him in March. Justice needs to be more consistent to protect Andrew Luck, something he did fairly well against the Pittsburgh Steelers on Sunday.
Defense: Jerraud Powers, cornerback
Powers is best in press-zone coverage, but he needs to become a better tackler against the run. New head coach Chuck Pagano, a defensive whiz in Baltimore, should help Powers improve.
Offense: Blaine Gabbert, quarterback
Coach Mike Mularkey has done a tremendous job with Gabbert, who has looked much improved through the first two games of the preseason. It's a good thing, because the Jags probably can't count on much (at least early on) from running back Maurice Jones-Drew, who is holding out and has yet to report to the team.
Defense: Clint Session, outside linebacker
Session is currently on the physically-unable-to-perform list after dealing with multiple concussions in 2011. If and when he returns, he'll bring the leadership skills and competitive spirit to make coordinator Mel Tucker's sneaky-good unit even better than it was last season.
KANSAS CITY CHIEFS
Offense: Kevin Boss, tight end
Boss is a good blocker and receiver who can make big plays when healthy. I think he'll be a key contributor to an offense that will be surprisingly good after a dreadful 2011. I wouldn't be surprised to see him frequently paired with Tony Moeaki in two-tight end sets, similar to what the Patriots run with Rob Gronkowski and Aaron Hernandez.
Defense: Anthony Toribio, nose tackle
The Chiefs have to stop the run on the other side of the ball. Toribio, who has great technique, could really help out on first and second downs and should beat out first-round draft pick Dontari Poe.
BONUS: Linebacker Justin Houston, a third-round draft pick from 2011, is quietly putting everything together and should make good on his talent this season.
Offense: Clyde Gates, wide receiver
The Dolphins have a glaring lack of receiver depth. Gates, a former basketball player with just two years of college football experience at Abilene Christian, might be able to step up and help. He won't fill a No. 1 role, but he can catch the ball, boasts unbelievable speed and quickness, and is a good return man, to boot.
Defense: Vontae Davis, cornerback
Davis needs to be more consistent; he'll make a fantastic play, then fall asleep. He needs to play football and not worry about the little things, like taunting (or being taunted). New coordinator Kevin Coyle should be able to get some good production out of him.
NEW ENGLAND PATRIOTS
Offense: Marcus Cannon, offensive tackle
Matt Light has retired, while Brian Waters and Sebastian Vollmer are question marks. Drafted in 2011, Cannon was hampered by non-Hodgkin's lymphoma as a rookie. But now he's healthy, strong and good enough to be a dominant starter.
Defense: Devin McCourty, cornerback
The smart, fast and athletic McCourty went from sunshine to snow in 24 hours. After grabbing seven interceptions and making the Pro Bowl as a rookie in 2010, McCourty was, according to STATS LLC, targeted by opponents a staggering 110 times in 2011, giving up 66 completions and picking off just two. Cornerbacks are constantly shuttling between the penthouse and the outhouse; McCourty must have the mental fortitude to shrug off a bad year and rediscover what once made him great.
NEW YORK JETS
Offense: Jeremy Kerley, wide receiver
The fate of the Jets' offense hinges more on guys like Kerley than it does on Mark Sanchez, Tim Tebow or Santonio Holmes. Kerley is a Wildcat guy, a matchup problem who lacks great size and speed but who can line up as a receiver, running back or passer.
Defense: Yeremiah Bell, safety
Between Bell, Eric Smith and LaRon Landry, the Jets need to find a strong safety who can play the pass and complement stud cornerbacks Darrelle Revis and Antonio Cromartie. Bell is the best coverage guy of a relatively weak group.
Offense: Juron Criner and Rod Streater, wide receivers
I'm cheating a bit here, but the Raiders really need to pump up the receiving corps to complement their ground attack. Criner doesn't have a ton of speed, but he has the hands and catching ability to function as a great possession receiver. Streater is a late-blooming (he spent two years at Division III Alfred State before transferring to Temple) blazer who has the potential to make big plays and catch a bunch of touchdowns.
Defense: Tommy Kelly, defensive lineman
The immensely talented Kelly can dominate in the run and the pass, and should flourish in coordinator Jason Tarver's new defense.
Offense: Emmanuel Sanders, wide receiver
Sanders isn't very big, but he fits the Steelers' system and would do well as the second receiver if Mike Wallace were to miss any time. He could be the Antonio Brown of 2012.
Defense: Cortez Allen, cornerback
Allen is battling Keenan Lewis for William Gay's old job. Both are tall guys who run well, but Allen has the toughness and upside to beat out Lewis. Lewis is a steady player, but Allen can be exceptional. Whoever starts will be tested extensively by teams looking to avoid standout cornerback Ike Taylor.
SAN DIEGO CHARGERS
Offense: Ronnie Brown, running back
Coach Norv Turner loves to use his running backs in the passing game. The 30-year-old Brown might have lost a step, but he has the experience and pass-catching ability to contribute as a third-down back. Brown is a smart player who knows how to get open, and looked great in camp. Even if starter Ryan Mathews doesn't miss much time with a broken collarbone, Brown could prove to be one of the biggest free-agent signings of the year.
Defense: Antoine Cason, cornerback
Cason needs to clamp down on the big plays. Of the 29 passing touchdowns scored against the Chargers in 2011, Cason allowed seven. He looked much better in camp than he did last year. New coordinator John Pagano should help the fifth-year veteran continue to improve.
Offense: Chris Johnson, running back
Everyone knows Johnson's name, but I wouldn't blame anyone for forgetting it after a dud of a 2011 season in which he scored just four touchdowns. If the Titans want to do anything in 2012, they need the former stud to return to form, and I think he will.
Defense: Alterraun Verner, cornerback
Verner is not that fast or tall, but he does make plays; targeted 55 times in 2011, Verner allowed just 26 completions (47.3 percent), according to STATS. Offenses will likely test him as he attempts to fill the shoes of former starter Cortland Finnegan, who left via free agency.