EAGAN, Minn. -- The unusual summer of Minnesota Vikings tight end T.J. Hockenson took a new turn Wednesday when he sat out most of practice because of what the team attributed to lower back stiffness.

Hockenson missed the majority of camp drills during the previous three weeks because of an ear infection that he said affected his equilibrium. That condition has resolved itself, coach Kevin O'Connell said Wednesday, but Hockenson "very recently" reported his back symptoms to the Vikings' medical staff. O'Connell classified Hockenson's absence as "day-to-day" and did not rule out a return to the field as early as Thursday's joint practice with the Arizona Cardinals, but such a quick return seems unlikely.

"We're at that time," O'Connell said, "where we just want to be smart with guys we know we're going to be relying on and make sure that their preparation for [the regular season] is what we want."

Hovering over the pair of reported ailments is Hockenson's contract status. He is entering the final year of his original rookie deal, which the Vikings have been eager to extend after acquiring him via trade last season from the Detroit Lions. But there has been little progress in talks.

NFL players sometimes scale back their activity in training camp to exert leverage on contract talks; the Vikings experienced an example at the start of camp before linebacker Danielle Hunter signed a new one-year deal that included a $12 million raise.

O'Connell was asked Wednesday whether he was certain that Hockenson's absence was related to the injuries and not to his contract.

"My dialogue with T.J. in regards to his training camp, or whatever that's looked like, has really been about the ear infection first," O'Connell said, "and working through that, and some of his [rehab] work kind of popped up to maybe cause some lower back stiffness... He has not indicated to me one time that it is about that [contract status]. And look, we would love to have him in every drill. ... But we've got to have a process where we get these guys healthy, feeling really good to go compete as we head toward the season."

"But I'll say this: T.J. has been phenomenal in the meeting room, really leading that tight end room, and the side work he's done. The individual work, the work staying in shape, his lifts and conditioning. I don't have any reservations about him being ready to roll for [the regular season]."

Hockenson was asked earlier this week whether his contract status was affecting his absence from practice.

"No, that's not my focus," he said. "My focus is to be out here with these guys on Sept. [10] and be ready for September and be ready for game days on Sunday."