Robert Mathis' injury leaves AFC South even more up for grabs

Coaching changes in Tennessee and Houston. An ongoing reclamation project in Jacksonville. As the rest of the AFC South scrapped this offseason to find its footing, the Indianapolis Colts stood confident in their role as division favorites, coming off an 11-5 season that gave the franchise its first playoff victory since 2009.

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Not even a full week into the regular season, though, perception may have changed.

Pro Football Talk reported Monday that Colts OLB Robert Mathis, already serving a four-game suspension, suffered a torn Achilles while working out in Atlanta. That injury will sideline the heart and soul of Indianapolis' defense for the remainder of the 2014 season.

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Mathis is coming off a spectacular 19.5-sack season that earned him a first-team All-Pro spot and Pro Bowl berth. The Colts were hoping to cobble together some semblance of a pass rush in Weeks 1 through 4, with Mathis set to provide an in-season boost after that. Instead, it's time for Plan B, which is ... unclear, as of Sunday night's loss to the Broncos. Indianapolis managed one sack of Peyton Manning but mostly failed to generate consistent pressure.

Second-year linebacker Bjoern Werner stepped into the starting lineup vs. Denver and was on the field for 62 of 77 snaps, according to Pro Football Focus. He was ineffective off the edge, however, finishing without so much as a QB hurry.

Save for a rapid improvement there, the emergence of an unexpected star like Andy Studebaker or Cam Johnson, or a roster addition, the Colts do not have any obvious answer to replace Mathis' production. Given that GM Ryan Grigson orchestrated the Trent Richardson trade last season, a similar move for a pass-rusher probably cannot be ruled out, however unlikely it may be.

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No matter what's next for the Colts, the Mathis injury is a devastating blow. Were it not for Luke Kuechly and J.J. Watt, Mathis could have stolen the Defensive Player of the Year award last season. He was again expected to be a linchpin for an Indianapolis D that appears average at best otherwise.

"We'll get through this," Chuck Pagano said back in May when Mathis was suspended. "We'll come together as a team, we'll come together as a family, we'll come together as an organization and we'll get through this. We love and respect Robert Mathis. He's a horseshoe guy, he's a pillar guy.

"Like I said before, we've got his back. Everybody in this organization has his back, and we'll get through this and at the end of the day, we'll all be better for it."

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Envisioning a future where Mathis' absence actually helped the development of Werner et al., was more realistic in a four-week window. Now, the Colts will be scrambling to come up with an answer.

Their search leaves the door open for another AFC South foe to swipe the division title away. Jacksonville's second-half collapse at Philadelphia reiterated that Gus Bradley's team may still be a year or two away from true contention. The same may not be true for the Titans, who stormed to a dominant Week 1 victory at Kansas City, or the Texans, who began their attempt to erase the sting of last year's 2-14 season by dropping Washington.

If the Colts' grasp on the division was tenuous heading into the season, it may be nonexistent before long. Mathis was that important to this roster -- arguably the most important Colts player behind Andrew Luck. Luck alone leaves enough reason for Indianapolis to believe it can defend its division title. Heck, he almost single-handedly willed the Colts to several victories last season.

But any arguments that the Colts were ready to take the next step as conference and Super Bowl contenders are on hold for now, at least until someone steps up to replace Mathis. Whether that happens or not, the AFC South is set to be a free-for-all.