Jets second-year cornerback Dee Milliner did not practice Wednesday after experiencing some tightness in his left hamstring. Milliner missed three games last year with a hamstring injury.

Injuries have been an issue for Milliner in his young career. He missed all spring last year after shoulder surgery. He missed significant time in training camp with an Achilles injury and then suffered the hamstring injury during the season.

Ryan repeatedly has said he believes all that missed practice time hurt Milliner’s development. Ryan did not sound happy that Milliner is on the sideline again.

“He has to understand that he has to be in extraordinary shape,” Ryan said. “His challenge is to be in world-class shape because we have to have you out there. He needs to be out there. He needs to get work because that’s how he’s going to get better.

“He’s got to step it up because I think he has all the talent in the world.”

Milliner said he hurt the hamstring during Monday’s practice and said he sat out for “precautionary” reasons. He does not believe the injury is serious.

With Milliner down, Ras-I Dowling saw time with the first-team defense at cornerback.