While New England Patriots tight end Rob Gronkowski is making strides in his return from back surgery, just how soon he’ll rejoin the team on the field remains to be determined, according to Michael David Smith of Pro Football Talk.

Ed Werder of ESPN has reported that Gronkowski has resumed light workouts, adding that people who have been working with the tight end describe him as being in good spirits while making significant progress.

This is all certainly good news, but Smith points out that it does not guarantee that Gronkowski will progress to the point where he’s healthy enough to suit up for the Patriots’ season opener on September 8. While he’s making progress, there’s cause for concern when you look at Gronkowski’s injury history. Smith points out that when Gronkowski underwent surgery in September of 2009 it cost him his entire senior season.

Gronkowski’s return becomes all the more important for the Patriots due to Aaron Hernandez’s arrest and the loss of players such as Wes Welker and Brandon Lloyd on offense. New England is reportedly getting offseason addition Tim Tebow snaps at tight end, but his role remains to be determined.