The Colts will be without CB Jerraud Powers, who was placed on injured reserve Monday. (US Presswire)

Injuries have hindered the Indianapolis Colts in 2012, especially on defense. Indy got more bad news Monday -- cornerback Jerraud Powers and nose tackle Drake Nevis will both be placed on injured reserve. 

Nevis is replaceable, having made just three starts. The Colts countered by activating rookie Josh Chapman, who has been on the reserve/non-injury list all season.

Powers is another story. He has been the starter at corner from Day 1 and was the only sure-thing in the Colts secondary. Indy later went out and snagged Vontae Davis to replace Cassius Vaughn, turning what was once a major weakness into a minor weakness. Hardly a ringing endorsement, but the Colts were building on a defensive secondary that struggled mightily in 2011.

But now Powers is down -- as is Davis, who has missed the last two games and is questionable this week -- and it probably comes at the worst possible time for Indianapolis, which will face the Patriots on Sunday. Vaughn and Josh Gordy will hold down one corner if Davis can't play, and Darius Butler will start in Powers' place. Both Gordy and Vaughn have been suspect in coverage, and they'll certainly be tested by Tom Brady. Butler was a ball hawk last week against Jacksonville, picking off two passes and recovering a fumble.

No matter how you slice it, though, the Indianapolis defense could be in for a world of hurt Sunday in New England.

"You don’t know exactly how they’re going to use all those tight ends or how Wes Welker is going to get open, but he’s going to get in there and dance around and get open," interim coach Bruce Arians said Monday of the Patriots offense. "You’ve just got to have enough pass rush and patience to get there and make sure you tackle extremely well."

For more up-to-the-minute news and analysis from Colts blogger Evan Hilbert, follow @CBSColts.