Getty Offensive guard Joel Bitonio of the Cleveland Browns. The Detroit Lions have a fairly serious problem on their hands with regards to the offensive line. Detroit lost two starters on the interior, as center Frank Ragnow retired in early summer, while right guard Kevin Zeitler left in free agency for the Tennessee Titans . Graham Glasgow moved from left guard to center in an offseason reshuffling. The Green Bay Packers in a Week 1 drubbing of Detroit exploited those changes along the line,