Defensive end Jonathan Allen left Sunday's game in the first quarter. (Jonathan Newton/The Washington Post)

The Washington Redskins received good news Tuesday about the health of Jonathan Allen. The third-year defensive lineman got a second opinion on his injured left knee, and the exam did not reveal a major problem or tear, according to a person with knowledge of the situation who spoke on the condition of anonymity.

Allen suffered a sprained medial collateral ligament in Sunday’s season-opening loss at the Philadelphia Eagles, but the injury is not expected to be a long-term issue and there is optimism that he could return sooner than later. On Monday, Coach Jay Gruden called Allen “week-to-week.” The Redskins face the Dallas Cowboys in their home opener Sunday, and it’s unclear whether Allen will be available.

Allen is a key piece of a defensive line that is the strongest unit on the team. The group, however, is thin after the organization kept just five linemen at the 53-man roster cutdown. Allen’s status remains a concern, and backup lineman Caleb Brantley is dealing with a foot injury that Gruden also called week-to-week. The team added defensive linemen T.Y. McGill on Tuesday.

Allen was the No. 17 pick of the 2017 draft, but he missed all but five games of his rookie season with a Lisfranc foot injury. He had 61 tackles and eight sacks in 2018 while playing all 16 games.

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