Ballard was coming back from a different catastrophic injury. In the first game of last season, Ballard tore his ACL, ruling him out for the year.
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In his rookie season in 2012, the Mississippi State product rushed for 814 yards and two TDs on 211 carries. Ballard reported to camp Wednesday and said he had passed his physical.
Former Colts running back Donald Brown signed with the Chargers this offseason. The team brought back Ahmad Bradshaw, who missed all but three games last season. Indianapolis also has veterans Chris Rainey and Trent Richardson.
- Alex Hampl