Robinson strained his right hamstring in practice Thursday. It's the same leg that kept him out during organized team activities.
A second-round draft pick from Penn State, Robinson had been one of the stars of training camp. But his injury may keep him out for the rest of camp and maybe the entire preseason.
Because of injury and suspension, Jacksonville was down to six receivers for Friday's practice.
Cecil Shorts III (hamstring), Tandon Doss (ankle) and Damien Copeland (wrist) are out indefinitely. Ace Sanders has taken a leave of absence to seek counseling following his four-game suspension for violating the league's substance-abuse policy.
Rookie receiver Marqise Lee got Friday's practice off.