A seventh-round draft pick in 2014, Johnson needs to pass a physical to practice when training camp begins Friday.
The Jaguars did not reveal the nature of Johnson's injury, but he missed time during organized team activities with a back injury.
With the addition of second-round draft pick T.J. Yeldon and fellow running back Bernard Pierce, Johnson already was buried on the depth chart heading into camp. Now he won't even be on the field when it opens.
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