Defensive end will miss 3-6 weeks because of knee injury

MACOMB, Ill. -- Rams defensive end Tyoka Jackson will be sidelined three to six weeks with cartilage damage in his right knee, putting his status for the season opener in jeopardy.

Jackson was to undergo arthroscopic surgery either Wednesday night or Thursday morning. He returned to St. Louis earlier Wednesday for an MRI that revealed the damage. He was injured earlier in the week but couldn't pinpoint the source.

"Talking to him, he didn't know how he did it," coach Mike Martz said. "It just happens. He kept working on it, but it kept getting more sore, so he kind of had to back off a little bit."

The Rams won't know until after the surgery how long Jackson will be out.

"That just kind of depends on how bad the tear is," Martz said.

"The worst case scenario is it's going to be a while, but knowing Tyoka I wouldn't think we'd miss him in the opener."

The 6-2, 280-pound Jackson played in all 16 games as a reserve at both tackle and end last year and had three sacks.

-- From wire reports