Green Bay — Clay Matthewsdoesn't know why his knee became sore after a couple of camp practices, but he said it is not a carryover from his off-season work and doesn't think it's anything serious.
The Green Bay Packers linebacker said Friday he was taking the advice of team physician PatrickMcKenzie and sitting out to make sure the knee doesn't get worse. He said it's possible he could play in the New England game Thursday, but his return has not been determined.
He isn't expected to take part in the practice Saturday night at Lambeau Field, which means by Monday he will have had eight days off.