ALLEN PARK, Mich. -- Defensive end Ziggy Ansah, the Detroit Lions' first-round pick in April, has been diagnosed with a concussion, according to the club's injury report Wednesday.

Ansah has been at practice the past two days but did not participate Wednesday. He ran with trainers watching during the portion of practice open to the media.

His status for Sunday's season opener against the Minnesota Vikings is uncertain. When asked how much practice time Ansah would need this week to play Sunday, Lions coach Jim Schwartz only responded with, "We'll see."

Earlier in the week, Schwartz said Ansah, who played at BYU, "got a lot of reps early in camp."

If Ansah is unable to play Sunday, Detroit would likely look to either Willie Young or Israel Idonije to fill in. The only other player listed on the injury report was safety Louis Delmas (knee).