Shanahan, addressing the media at the end of an organized team activity session, was asked about Westbrook, who visited the Redskins last week.
Westbrook isn't in a hurry to sign with a team and is weighing his options. His agent, Todd France, said some interested teams are expected to pick up communication next week.
Westbrook had spent his entire eight-year NFL career with the Philadelphia Eagles, but the team released him in March after an injury-plagued 2009 season. He sustained two concussions and finished with just 274 rushing yards in eight games.