Posted by ESPN.com's Tim Graham
One week into the season, all four AFC East clubs are missing an important linebacker.
Let's take a look at each void and who is filling it.
New England Patriots
Who's down? Inside linebacker Jerod Mayo.
Why? Injured right knee.
How long? Reportedly six to eight weeks.
Analysis: The Patriots aren't as forthcoming with injury information as other teams, so we don't know for sure how long Mayo will be sidelined, but his absence will hurt.
The Boston Globe's Monique Walker and Christopher L. Gasper, citing two unnamed sources, report Mayo suffered a sprained medial-collateral ligament. Sources differed on the length of Mayo's recovery time, with eight weeks the longest estimate.
The Patriots turned over the defense, losing four significant leaders to retirement or trades. Mayo's importance in the transition was underscored by the fact his teammates elected him a defensive captain.
Mayo is the reigning NFL Defensive Rookie of the Year for amassing 139 tackles.
Guyton and Thomas filled in for Mayo on Monday night but were shaky.
Who's down? Middle linebacker Paul Posluszny.
Why? Broken left arm.
How long? Six to eight weeks (updated)
Who steps in? Marcus Buggs.
Analysis: What's up, Doc? That's what the Bills are asking because Buggs doesn't play anything like Posluszny.
The injury Posluszny suffered in the second quarter Monday night is similar to the one that ended his rookie season after three games in 2007. But this occurrence, while it required surgery Wednesday, it isn't as serious. Bills coach Dick Jauron said the Bills hope Posluszny will be back on the field by the season's midpoint.
Posluszny, the Butkus Award winner at Penn State four years ago, is a Bills captain. He led them with 129 tackles last year. He also had an interception, a forced fumble and a recovery.
It's a potentially season-changing blow to the lineup.
New York Jets
Who's down? Outside linebacker Calvin Pace.
How long? Four weeks.
Who's in? Vernon Gholston.
Analysis: Pace is serving a four-game suspension for violating the NFL's policy on performance-enhancing substances and can't even hang out at the Jets facility.
Gholston made four tackles, including one for a loss, but he's not even close to the player Pace is. Pace was a hellion last year, recording seven sacks, 12 tackles for losses and five forced fumbles.
The Jets proved they can make so without him, but they'll be even scarier when he returns.
Who's down? Outside linebacker Matt Roth.
Why? Groin -- we think.
How long? Six weeks.
Who's in? Jason Taylor.
Analysis: This is the least significant of the four situations because Roth wouldn't have been an every-down player anyway, and his replacement is one of the greatest defenders in team history.
Roth, last year's starter on the strong side, arrived at training camp with what was first called an illness but was later classified a groin injury. He also wanted a new contract. Regardless, he didn't practice with the team. The Dolphins placed Roth on the injured list, meaning the soonest he must sit out the first six games.
The intention when Taylor signed with Miami was to use him on passing downs. Now the 35-year-old is playing almost every down. He recorded a sack in the season opener.