"The Chiefs lost a valuable reserve linebacker and special-teams player Tuesday when Brandon Siler tore his Achilles' tendon. The Chiefs made no announcement, but Siler is lost for the season.

Siler, who was signed last month as a free agent from San Diego, was injured on the final play of Tuesday's practice. He was trying to make a tackle on a goal-line play when he was injured.

He has had surgery to reattach the tendon.

"I think we have good depth, but it's always tough to lose a linebacker or any kind of player," linebacker Derrick Johnson said. "This is a violent sport and injuries happen, and that's the unfortunate part."

Johnson and Jovan Belcher are the starters at inside linebacker. Veteran Demorrio Williams, a former starter, is the backup at Johnson's spot and now may be asked to back up at Belcher's position as well.

"If they need me to play there, I'd be happy to play there," Williams said. "I'm not going to say it's an opportunity. I never did think (Siler) was (ahead) of me."

Siler's injury could open a roster spot for one of the younger linebackers, perhaps Justin Cole. Cory Greenwood is another backup at inside linebacker, but he will probably make the team anyway because he is one of the Chiefs' best special teams players."