Vikings coach Leslie Frazier told Detroit reporters today on a conference call that Brett Favre has yet to pass a concussion test but that another could be administered later Thursday or Friday. Frazier said the latest Favre could be tested would be Saturday. 

Favre failed the baseline neurological examt late Wednesday. Frazier has said if Favre is healthy he will play on Sunday against the Lions in what the quarterback has said will be the final game of his 20-year career.