INDIANAPOLIS — The Indianapolis Colts’ secondary is becoming a primary concern.

One day after allowing Detroit quarterback Matthew Stafford to throw for 340 yards, three touchdowns, and blowing the lead in the final 37 seconds, coach Chuck Pagano started putting the pieces back in place for a Week 2 matchup in Denver.

Right now, just putting together a starting lineup is a challenge.

“T.J. Green had an MRI and has a mild MCL sprain and he’ll be week to week,” Pagano said Monday. “Patrick Robinson had a concussion, so, of course, he’ll go through the protocol.”

That’s two more starters who may have to sit out this week.

It’s already been that kind of season.

Indy (0-1) finished Sunday’s game without its top three cornerbacks: Vontae Davis (ankle), Robinson and Darius Butler (ankle). Davis and Butler were both inactive Sunday, and Davis is likely to be inactive again this week.

The news is more promising for Butler, who is expected to practice Wednesday, but Robinson’s status remains unclear.

At safety, things are nearly as bad.

Green lasted 28 plays in his NFL debut before injuring his right knee. Winston Guy, Green’s replacement, left with 4:11 to go with what appeared to be a lower left leg injury, but apparently avoided anything serious. Clayton Geathers, initially the projected starter, returned from an injured right foot to do limited work at practice last week. His workload may be upgraded this week.

But with so many dinged players and so much still up in the air, the Colts have been busy revising their own contingency plans.

“You definitely have to over-communicate because we’ve got some guys that haven’t even been in the building for seven days — and they’re playing,” inside linebacker D’Qwell Jackson said. “But that’s the National Football League. At one point during the game, you’re just seeing bodies on the ground every play and you were hoping you weren’t next.”

Stafford took advantage Sunday. Next up is Denver quarterback Trevor Siemian .

For the Colts, it’s going to be a way of life for a while longer.

The situation became so dire last week that even team owner Jim Irsay acknowledged Indy’s offense would probably have to continue outscoring opponents until some key defensive players return.

The defense hopes to change that perception sometime this season, but only reinforced that image by giving up 39 points and allowing the Lions to drive 50 yards in 33 seconds to erase Indy’s only lead of the game.

“People always say this is an offensive team, and we’ve been saying, ‘Let’s take that off their hands and be a defensive team,'” said Pro Bowl safety Mike Adams, the anchor of the secondary and one of the few still relatively healthy players. “Yesterday, we failed.”

There were plenty of explanations for what went wrong.

The Colts missed too many tackles on the Lions’ final drive, and earlier in the game, too.

And while Jackson was talking more than usual on the field, Adams spent more time directing teammates such as cornerback Darryl Morris, signed last Monday, and cornerback Rashaan Melvin, signed last Wednesday, about where to go.

“It wasn’t chaos out there, Chuck just told me to line them up and keep them calm back there,” Adams said. “Once they lined up, it was pretty easy.”

Until the Lions started executing, that is.

But Adams, a 13-year veteran who acknowledged he’s never seen a secondary hit this hard, won’t accept excuses. He expects the Colts to overcome the injuries and play well.

“Look, guys are getting paid because they’re capable, so we expected them to step up and do their job,” Adams said. “That’s how I got my job when I was a young pup.”


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