Jackson missed Tuesday's practice with an undisclosed injury, Mike Chappell of Fox 59 Indianapolis reports.
While the nature or severity of Jackson's injury isn't clear, his absence from practice is less than ideal for a Colts squad that will head into its preseason opener Saturday versus the Bills with top running back Jonathan Taylor (ankle) on the PUP list and Zack Moss out with a broken arm. In light of the injuries to Taylor, Moss and Jackson, the Colts signed Jason Huntley on Wednesday to add depth to the running back room. If Jackson is able to quickly move past his injury, he could have a significant role with the Colts if Taylor remains sidelined for the start of the regular season. However, the Colts are also reportedly in talks to sign free agent Kareem Hunt, so they may add a veteran instead of giving Jackson a look in a leading role in that scenario.