Posted by ESPN.com's Ted Miller
Arizona tight end Rob Gronkowski is doubtful for the opener against Central Michigan because he hasn't participated in any practices this week due to a back injury, according to the Arizona Daily Star.
Gronkowski didn't dress for Wednesday's practice, according to the newspaper, and has not yet been cleared to play.
Gronkowski, a leading candidate for the John Mackey Award, strained his back during the offseason and aggravated the injury at the beginning of preseason camp, which he missed almost entirely.
Coach Mike Stoops has called Gronkowski's condition "week to week."