The Patriots defense just can't catch a break. They can, however, catch a tear.
They're now up to two of them on the season—first to defensive tackle Vince Wilfork's Achilles tendon, and now to linebacker Jerod Mayo, who has suffered a torn pectoral muscle that will likely end his season. The injury was first reported by Les Carpenter of Yahoo! Sports and later confirmed by the Patriots:
They will certainly miss his presence on the field—how could they not? He has played 96.4 percent of the defensive snaps for them this season and has never played less than 89 percent of the snaps in a season.
Mayo played all but eight defensive snaps for the Patriots before his injury, and as such, was a mainstay in both the base defense and the sub-package.
As the weak-side linebacker, Mayo was asked to be a jack of all trades. He didn't rush the passer very often but still managed to generate five total pressures and reached the quarterback twice.
Mayo logged a sack of Buccaneers quarterback Josh Freeman late in the first quarter. It wasn't a designed pass rush; Mayo's responsibility on the play was simply to read the running back.
The Buccaneers set up play-action with a fake to running back Doug Martin, who came up in protection on the edge once Mayo started to rush toward the line of scrimmage. Freeman dropped back and looked around, but couldn't find anyone open.
Mayo stayed with it, reading the quarterback as he kept his eyes on the backfield. Once Freeman began running away, he spun off Martin's block and swooped in for the sack.
Mayo wasn't replacing Wilfork, but he was making an impact in the running game as well. Of his 35 tackles, 16 were considered stops (plays in which the offense failed to stay on schedule).
His instincts were some of the sharpest on the Patriots defense, probably because his film study habits were among the best on the team.
Against the Bengals, Mayo sniffed out a pass to running back Giovani Bernard in the flat despite a lot of traffic in his area.
The two tight ends were running drag patterns that crossed paths right in front of Mayo. The receivers in the slot ran a post pattern right behind him.
Yet there Mayo stood, reading and reacting.
Once he saw Bernard in the flat, he darted in that direction and wrapped up the back for a short gain.
Rookie linebacker Jamie Collins has not played much (52 total snaps this season), but he has versatility as an outside linebacker, having played on both the weak side and strong side in the preseason. That could lead to an increased role in the base defense.
Fourth-year veteran linebacker Dane Fletcher is another candidate for more responsibility. He has played just 11 defensive snaps this season, six of them against the Saints after Mayo's injury.
As for who gets the extra run in sub-packages, while it's been primarily Dont'a Hightower and Brandon Spikes playing next to Mayo, Collins was in as the second linebacker in the above play and could be asked to carry play a bigger role in coverage.
That being said, it's not always a plug-and-play scenario at linebacker.
"As we build through the season, some players have kind of one specific responsibility and sometimes we have other players that have more than one," said Patriots head coach Bill Belichick. "Some of that depends on the player, his skills, his experience, what else he has relative to the kicking game as an example, roles in sub-defense or other situational defenses. Sometimes that changes over the course of the season, from week to week."
The Patriots like to change what they do defensively in terms of their scheme from one week to the next. They will run a mix of fronts, pressures and coverages to keep an opponent honest, showing them things they haven't seen before on tape that they may not necessarily be prepared for.
Part of that involves players moving around the defense and lining up at different spots. Mayo has played many different spots in his career, from 3-4 inside linebacker to 4-3 middle linebacker to 4-3 outside linebacker, on the weak side and on the strong side in every scenario.
"When we get taught, we don't get taught as a Mike or a Sam or a Will or a Jack, we're just 'backers," said Hightower. "The best way and the easiest way to learn something is to know the concept of it, so once I know the concept of something, I know what each position does, and we all do that. Spikes knows the Sam, Jamie knows the Will, Dane knows the Jack. Everybody can move around, and it's easier that way, and it's easier for us to scheme different teams."
His on-field presence will be missed, but much like with Wilfork, it won't be about one player filling the void; it will probably be replacement by committee.
The one aspect of Mayo's presence that could be missed most, however, is his leadership. Piling on the losses of both Wilfork and Mayo, the Patriots have lost both of their defensive captains. Safety Devin McCourty was a captain in 2011 and 2012 and could resume that role. Defensive end Rob Ninkovich is one of the elder statesmen of the Pats defense and could be asked to step into a leadership role as well.
Mayo's leadership spills over onto the field, too. For the past four-plus years, Mayo has worn the green-dot helmet for radio communication with the Patriots coaching staff. He has more experience with the New England defense than anyone else, save for possibly Wilfork.
That's a role that will also most likely be filled by Hightower, who earned some practice wearing the green dot in the preseason and in training camp.
"I look forward to it," Hightower said. "I talked to (defensive coordinator) Matt Patricia, I talked to (linebacker coach) Pepper Johnson about it, so it's definitely something that I knew down the road that if something ever happened, I knew that I would have to step up and do it. I'm not nervous about it, it's something that I've done before, maybe not in the NFL, but I've done it before, so everybody's behind me and they support me, so it's all I can ask for."
Getting his teammates lined up will be important, and the tough part for Hightower is that we'll likely only notice if something looks wrong with their communication, not if things continue to go smoothly.
Whether it's the green dot, his leadership or his role in the defense, Mayo has done it all for the Patriots over the years. Replacing him won't be easy, but the Patriots have players who can fill all of his roles.
"Who knows exactly how the wheel is going to spin," Belichick said, "who is going to be where, but we all have to prepare for that."
Erik Frenz is also a Patriots/AFC East writer for Boston.com. Unless otherwise noted, all quotes obtained firsthand or via team news releases.