ALAMEDA, Calif. (AP) — Oakland Raiders rookie quarterback Derek Carr returned to practice three days after being knocked out of a preseason game with a concussion and sore ribs.Carr practiced on a limited basis Monday and his status for the upcoming exhibition game in Green Bay on Friday night remains a question.Carr got hurt in the fourth quarter last Friday against Detroit when he was hit from behind by Larry Webster. Carr got up and immediately pointed at his ribs but later said the concussion was more of a concern. Carr has never had a concussion previously in his career.Carr played well before the injury and even got one drive in with the starting offensive line and receivers.Kansas City’s Charles injured leaving dormKANSAS CITY, Mo. (AP) — Jamaal Charles made it through every hit from Derrick Johnson, every shot from Eric Berry and every tackle from the rest of the Chiefs’ defense during three weeks at Missouri Western.It wasn’t until he was leaving their training camp home that he got hurt.Manziel struggles in Browns’ loss to RedskinsLANDOVER, Md. (AP) — Johnny Manziel and Brian Hoyer didn’t make Mike Pettine’s decision any easier.