Calvin Johnson on concussions, injuries - Sports Illustrated
Lions great Calvin Johnson, 30, retires from NFL
NFL: Detroit Lions star Calvin Johnson set to retire
2016 NFL season division-by-division preview
Beloved Calvin Johnson was once-in-a-generation talent, and man
Lions great Calvin Johnson, 30, retires from NFL
Calvin Johnson retires with record-tying five 200-yard games - Sports Illustrated
It's true: Lions' Megatron Calvin Johnson will retire from football at age 30
Calvin Johnson retires from NFL