DETROIT (AP) - The Detroit Lions have been officially looking for a coach for a week. The candidates to replace Jim Schwartz include: San Diego Chargers offensive coordinator Ken Whisenhunt, Baltimore Ravens offensive coordinator Jim Caldwell and Cincinnati Bengals offensive coordinator Jay Gruden. A person with knowledge of the process tells The Associated Press that the Lions asked for permission to interview Gruden. The person - who spoke Monday on condition of anonymity because the team hasn't made information about the search public - says Minnesota, Tennessee and Washington also asked to speak with Gruden. The Lions interviewed Caldwell last week and have expressed in Whisenhunt to replace Schwartz, who was 29-51 in five years.