Competing for that playing time are Darnell Savage, Caleb Ransaw, Andrew Wingard, and Antonio Johnson. The Jaguars also have rookie Rayuan Lane, who could help on special teams right away, and Daniel Thomas, who has been a core teams contributor for the Jaguars.

Jacksonville Jaguars defensive lineman Maason Smith will begin training camp on the team's Active/Physically Unable to Perform list, the team announced Tuesday.

Before the Jaguars' first training camp practice, let's take a look at four positional battles on defense to watch closely.