Lions wide receiver Calvin Johnson announces retirement after nine
Calvin Johnson: Former All-Pro invited to Detroit Lions camp next
Fantasy impact of Calvin Johnson's retirement
Calvin's retirement gives Lions $11M more for 2016
Calvin Johnson says he learned to play through concussions during
Calvin Johnson's beef with the Lions, and his $1.6M demand
MLive.com - Here's what Barry Sanders has to say about Calvin
Calvin Johnson content in retirement, not 'treated the way I
Lions' star WR Calvin Johnson to retire - Bucs Report