Sam Bradford's lingering left knee injury will force him to miss Wednesday's practice, putting his status for Sunday's NFC North opener against the Lions in doubt.

Bradford has not practiced since Sept. 21, a day before he flew to Pensacola, Fla. to visit Dr. James Andrews for a second opinion on his knee.

"I'm going to give him the day off today," head coach Mike Zimmer said Wednesday. "But we're doing everything we can to get him ready to play Sunday. We'll just give him one more day of rest."

The Vikings did not make Bradford available Wednesday, when the starting quarterback typically addresses reporters. Case Keenum, who would start for Bradford a third time Sunday, spoke with reporters in the locker room instead.

Bradford has said he's dealing with a "non-contact" injury suffered against the Saints on Sept. 11, when he played every snap and posted a 143.0 quarterback rating in the Vikings' win.

The second opinion received Friday confirmed what the Vikings believed, a source told the Star Tribune's Ben Goessling, which is Bradford's swelling is not due to structural damage to his twice-surgically repaired knee.

Defensive end Stephen Weatherly also wasn't practicing for the Vikings on Wednesday.