Colts position breakdown: Does Pagano's job rest on defensive line's play?

"It's our Achilles heel right now. We either get it fixed or it will be somebody else getting it fixed."

That's Indianapolis Colts coach Chuck Pagano. Talking about his run defense. And, more importantly, talking about his job security.

He knows. His owner knows and his general manager knows. Heck, the entire city of Indianapolis knows. They've watched the same horror flick play out over and over, ending in the same, brutal fashion each time. They've watched the New England Patriots punish the Colts' defensive line in four consecutive meetings since Pagano took over in 2012, leaning on the same, trusty blueprint for each massacre.

They've run the football down the Colts' collective throat each time while Pagano's defensive line tries helplessly to stop it. They've never come close. It's been ugly and it's been alarming.

The last time we saw the Colts' defensive line, they were the primary culprit in Indy's humiliating 45-7 AFC Championship Game loss in Foxborough. No positional group ended the season on a lower note. None enters the 2015 campaign with more to prove. And none will be more vital in the Colts' attempt at The Next Step, which happens to be The Super Bowl Step.

This we know: If the Colts don't get it fixed, they'll have no shot at beating New England. They'll have no shot at making the Super Bowl.

And Chuck Pagano might be looking for a new team to coach next year.

Pagano, general manager Ryan Grigson and owner Jim Irsay have all been blunt in their assessment of the run defense in recent months. Irsay's words are especially telling. He rattled off the Patriots' numbers like he knew them cold — because he does. That's how much they gnaw at him.

"It's concerning, obviously, when you have (allowed) 657 yards in three games (against New England)," Irsay said at the NFL's owners meetings in March in reference to the last three meetings. "You have 219 yards a game against you on the ground and that doesn't bode well. I think it's something Chuck wants to fix and the defense wants to fix because … the first thing we talked about is, hey, the first thing we do is stop the run and then we get after the passer."

This is what will determine Pagano's livelihood in Indianapolis. He's a coach in the last year of his contract with no guarantee of a return. He's the defensive mind Irsay and Grigson plucked from Baltimore in 2012 and tasked with rebuilding the Colts in the mold of Ravens' vaunted unit. In his team's past two playoff exits, both in New England, Pagano's defense was embarrassed.

In four meetings with New England, the defense has allowed 771 rushing yards and 15 touchdowns.

It can't go on for much longer. Irsay's made that clear.

As for the personnel, Indianapolis bid farewell to two defensive line starters (Cory Redding and Ricky Jean-Francois) and added former St. Louis Ram Kendall Langford, who offers promise but totaled just one sack and 14 tackles in 494 snaps last season. (It's worth noting Langford was fighting for snaps on one of the league's best defensive lines.) The Colts instead chose to invest in the line in the draft, adding two Stanford products: Defensive end Henry Anderson at No. 93 — a player some pundits called one of the top sleepers in the draft — and defensive tackle David Parry with the 151st pick. Training camp will offer our first real glimpse into what sort of impact those two will have this season.

But the man this all hinges on is Art Jones. He wasn't himself last season — "Frustrating as hell," he called a high ankle sprain that cost him most of the year — and he enters this 2015 season with as much to prove as any player on the Colts' roster. The Colts didn't give Jones a $33 million contract in 2013 to watch him start only three games and make 15 tackles.

They gave him $33 million to stop the Patriots' run game in the playoffs.

For Jones, and for this group, the missive is simple: Time to step up.

Who's back: NT Josh Chapman (385 snaps, 0 sacks, 17 tackles); NT Zach Kerr (289 snaps, 3 sacks, 10 tackles); DT Art Jones (371 snaps, 2 sacks, 15 tackles); DT Montori Hughes (198 snaps, 0 sacks, 10 tackles); DT Kelcy Quarles (23 snaps, 1 sack, 0 tackles); DT Jeris Pendleton (last played for the Colts in 2013).

Who's gone: Cory Redding (757 snaps, 4 sacks, 11 tackles); Ricky Jean-Francois (647 snaps, 3 sacks, 21 tackles).

Who's new: DE Kendall Langford (494 snaps, 1 sack, 14 tackles for the Rams last season); DE Henry Anderson (rookie out of Stanford); David Parry (rookie out of Stanford); DE Earl Okine (last competed for the Brooklyn Bolts of the Fall Experimental Football League).

Projected starters: Langford, Jones and Chapman.

Most to prove: Jones. By a long shot.

X-factor: Anderson. "A guy that could be here for a really long time," Grigson says of the hulking defensive end.

Stat to chew on: 4.6 and 12 rushing touchdowns vs. 3.7 and two rushing touchdowns. That's what the Colts gave up without Art Jones on the field last season (he missed seven games with a high ankle sprain) vs. what they gave up with him on the field last season. That's a big difference.

Quotable: "We have to do a better job as a whole — collectively, myself and the personnel, adjusting the schemes, adapting. Our mandate from our owner down is to be able to stop the run in January and make the adaptations during the game to stop the bleeding. Then we have to have players because those coaches can't go out there and play for the guys." — Ryan Grigson

"My goal this year is to be out there all 16 games. I'll be ready to rock and roll." — Art Jones

Call Star reporter Zak Keefer at (317) 444-6134 and follow him on Twitter: @zkeefer.