Due to a sprained right knee, Carolina Panthers' defensive end Julius Peppers is doubtful for Saturday's game against Dallas. Peppers missed his fourth straight practice Friday and likely will be replaced by Stanley McClover or rookie Charles Johnson in the lineup against the Cowboys. Peppers, who was injured in Sunday's win against Seattle, has been held to three sacks and had his streak of three straight Pro Bowl selections snapped this week. Safety Chris Harris returned to practice after missing Thursday's workout with a sore hip and is listed as probable to play against Dallas.