What are the three key camp issues facing each AFC East team?

BUFFALO BILLS

Offense: Relying on rookies early

The Bills pressed reset this offseason with a franchise overhaul that included a new quarterback in rookie EJ Manuel. But he’s not the only potential rookie starter on offense, as Buffalo might turn to receivers Robert Woods and Marquise Goodwin. Seventh-round tight end Chris Gragg is also a name to keep an eye on as Scott Chandler works his way back from injury (should be 100 percent for camp). Woods brings polish while Goodwin and Gragg have no shortage of speed, but can they turn those traits into immediate contributions? And if Manuel wins the starting role under center, can he replicate the recent success of other rookie quarterbacks?

Defense: Finding a third cornerback

The Bills were unable to come to terms on a long-range pact with safety Jairus Byrd before Monday’s deadline, but that’s not the only secondary issue they’re facing. Beyond Stephon Gilmore and Leodis McKelvin, it’s unclear how the cornerback depth chart stacks up. Veterans Ron Brooks and Justin Rogers are candidates to compete for the nickelback job, and in a division that features a Tom Brady-led offense, a defense without capable cornerbacks is in major trouble.

Wild card: Scheme transition on both sides

There is optimism surrounding the new direction of the Bills behind coach Doug Marrone, but one inevitability of a coaching change is the transition from one scheme to another. On offense, the success might depend on quarterback play, whether it’s Manuel or Kevin Kolb under center. Defensively, new coordinator Mike Pettine faces the challenge of fitting the incumbent pieces into his scheme. If he can maximize the talents of Mario Williams, Kyle Williams and Marcell Dareus, the front seven should be formidable by season’s beginning.

MIAMI DOLPHINS

Offense: Martin on the left side

Jake Long is now a Ram, and the Dolphins are entrusting Jonathan Martin to fortify the left side of their offensive line. In limited reps as Ryan Tannehill's blindside protector in 2012, Martin struggled, showing an inability to consistently anchor and hold up against speed-to-power rushers. Martin was more comfortable on the right side of the line, but the Dolphins have enlisted veteran Tyson Clabo to take on that role this season. If Martin is unable to man the left tackle position, the Dolphins have limited in-house options to replace him.

Defense: Secondary

The Dolphins lost cornerback Sean Smith in free agency a year after trading away Vontae Davis. The presumptive starters for 2013, Brent Grimes and rookie Jamar Taylor, enter training camp coming off injuries (Grimes missed nearly the entire 2012 season), and it’s fair to wonder how much, if at all, the secondary has improved. At his best, Grimes is one of the top off-man cornerbacks in football, a pesky ball hawk with reactive athleticism. But if an Achilles injury lingers, the Fins are in danger of playing with a short-handed secondary.

Wild card: Miller ready for heavy load?

With Reggie Bush in Detroit, the Dolphins must turn to a new feature back, and the early buzz suggests Lamar Miller is the leader in the clubhouse to take on that role. Talent, specifically speed, won’t be the issue for Miller, but he’ll be tested by the rigors of a full workload. Daniel Thomas hasn’t proved to be the answer in the backfield, and although Mike Gillislee offers some ability, the Dolphins need Miller to emerge in order to ease the burden on Tannehill.

NEW ENGLAND PATRIOTS

Offense: Passing game chemistry

The Patriots face the prospect of starting the regular season without their top five pass-catchers from 2012, a tough chore for any offense. Although Tom Brady has shown a penchant for developing a rapport with new wideouts quickly, the turnover among his targets this year is substantial. The Patriots hope that Danny Amendola will replicate Wes Welker’s success, but the depth chart behind him is less certain. A trio of rookies, Aaron Dobson, Josh Boyce and Kenbrell Thompkins, will come under the microscope during training camp.

Defense: Possible Dennard fallout

The Patriots worked hard to retain their secondary from 2012, a group that made strides when Aqib Talib and Alfonzo Dennard became starters. Dennard, however, enters training camp on uneasy footing after a recent arrest for suspicion of a DUI, which could affect his on-field status. (He was already on probation for an April 2012 arrest.) If Dennard misses any time, the Patriots’ cornerback depth will be thinned and the depth chart reshuffled. For a group that finally seemed to hit its stride late last season, potential shuffling is not what it needs.

Wild card: Pass rush

Though the defense generated 37 sacks last season, an untimely no-sack, no-quarterback hit effort against Joe Flacco and the Ravens in the AFC Championship Game is difficult to forget. The Patriots passed on marquee veteran edge rushers this offseason, opting instead to rely on the development of young rushers and the selection of second-round linebacker Jamie Collins. Chandler Jones has a high ceiling, but he needs to build on the first half of his rookie season, during which he recorded all six of his sacks. Marcus Benard, who notched 7.5 sacks in 2010, is a player to keep an eye on.

NEW YORK JETS

Offense: Playmakers, anybody?

While all eyes will be on the quarterback competition this summer, there’s also a startling dearth of talent at the skill positions for the Jets, especially with questions surrounding Santonio Holmes’ foot. The Jets lack a dynamic tight end and are short on proven receivers. No matter who wins the quarterback competition, he won’t have much in the way of reliable playmakers to give the football. New running back Chris Ivory is the most exciting player on this offense and is likely to be prominently featured.

Defense: Milliner ready?

The Jets will be well-coached on defense, as Rex Ryan is one of the best at maximizing his talents. Although the defense held up in the secondary without Darrelle Revis, the pressure will be on rookie cornerback Dee Milliner to make the group even better than it was toward the back end of 2012. He was widely considered the top cornerback in the draft, but now he has the task of trying to make Jets fans (partially) forget that Revis is a Buc.

Wild card: Coples’ transition

Ryan can generate pressure through his defensive schemes, but the Jets have lacked a pure edge rusher in recent seasons. One vehicle to solve that issue is transitioning Quinton Coples from a down lineman to a stand-up linebacker role, a position that could fit with his skill set. Though Coples flashed as a rookie in 2012, it’s about consistency for the former first-rounder. At 6-foot-6 and 290 pounds, he has the frame to be dominant. The Jets will need him to provide a pass-rush spark in his second NFL season.