FRISCO, Texas — Four-time Pro Bowl centre Travis Frederick was placed on the non-football illness list by the Dallas Cowboys on Saturday because of a nerve condition that has kept him from playing this season.

The team also put receiver Terrance Williams on injured reserve because of a foot injury.

Those moves cleared two spots on the active roster before Sunday's game at Houston. One will be filled by defensive lineman David Irving in his return from a four-game suspension for violating the NFL's substance abuse policy, but the team said he didn't make the trip and wouldn't play against the Texans.

Frederick was diagnosed during the preseason with Guillain-Barre syndrome. The Cowboys initially kept him on the active roster, but now he will miss at least eight more weeks. He could possible return the final month of the regular season.

Williams will also miss at least eight weeks.

___

More AP NFL: https://apnews.com/tag/NFL and https://twitter.com/AP_NFL