ALLEN PARK, Mich. -- The Detroit Lions held rookie quarterback Matthew Stafford out of practice Wednesday because of his injured right knee.
The Lions chose not to reveal anything more than that.
Stafford, the No. 1 overall pick in the April draft, had his right knee twisted on a sack during last Sunday's loss at Chicago. He wasn't in the locker room Monday or Wednesday when it was open for the media, but he told reporters after the Bears game that he hurt the same knee in high school.
Even if Stafford can't practice again Thursday, Schwartz said that won't necessarily keep the quarterback out of the game.
"I don't want to set any hard-set rules," the coach said.
Veteran backup Daunte Culpepper took snaps with Detroit's first-string offense while Stafford watched, wearing a red No. 9 jersey, a Tigers cap, black shorts and shoes.
Culpepper competed to be Detroit's starting quarterback until he needed eight stitches to close a cut on his foot after the team's third preseason game.
Schwartz confirmed that wide receiver Calvin Johnson didn't practice Wednesday after missing the end of the Bears game with a leg injury. Schwartz wouldn't acknowledge that offensive tackle Gosder Cherilus was held out even though he was relegated to watching practice while reporters had access.
Schwartz broke free from his policy of not talking about banged-up players other than information he is required to provide in injury reports.
"It's a little different than other positions," Schwartz said. "I normally won't do that, but this day was a special day and it was a different set of circumstances."
The Lions also claimed safety Marvin White off waivers from the Dallas Cowboys and signed linebacker Zach Follett from their practice squad. To make roster room, the team released linebacker Darnell Bing and placed wide receiver Adam Jennings (ankle) on season-ending injured reserve.
Copyright 2009 by The Associated Press