The Jacksonville Jaguars defense has been dealt a big blow with linebacker Myles Jack landing on IR with a knee injury according to Ian Rapoport of NFL Network.

The more revealing part of Rapoport's tweet is that Jack has battled through a variety of different ailments this season. After signing the big contract extension, Jack has struggled at times and some were calling for him to be moved out of the Mike linebacker role.

Just a couple of weeks ago Jaguars defensive coordinator Todd Wash had to give Jack a vote of confidence saying he would continue in his current role.

“No,” Wash said during his press conference when asked if he has thought about moving Jack to outside linebacker via Sports Illustrated. “No, he is our Mike linebacker.”

One of Jack's big issues this season has been shedding blocks and if he has been dealing with some hidden injuries, it could be a big reason for the struggles.

“Well, I think it’s like everything else, there are times that we just have to keep hustling, working, getting off of blocks better. Taking on blocks and getting off of them,” Marrone said. “I think the one thing you see is that we had guys coming up and guys covering us up last week, and we were unable to get off blocks.

It's unclear if he is going to undergo surgery or just needs time to rest, but whichever way hopefully the extra time off can get him back to 100 percent. He can come back next year stronger and play like the guy who earned the big contract extension.

Last week it was Donald Payne who started at the Mike linebacker in Jack's absence.