Vikings center John Sullivan has back surgery, will miss at least eight weeks

Vikings center John Sullivan had back surgery Wednesday, and the team placed him on injured reserve/designated to return this morning. Under that one-time designation, he must sit out a minimum of eight weeks.

Sullivan, in his eighth season out of Notre Dame, sat out practices and preseason games the past three weeks because of back issues. The Vikings initially said it was "back spasms" and as recently as Monday coach Mike Zimmer said he wasn't concerned about Sullivan's injury, even saying that there was a chance that Sullivan would practice Tuesday.

But Zimmer said today that Sullivan had been dealing with a herniated disk and that his recovery from that injury recently plateaued. Yesterday, Sullivan underwent a procedure called lumbar microdiscectomy.

"He was doing better," Zimmer said. "He was running. Typically, you treat these conservatively because if you don't you could end up having the surgery. You want to take your time to see if it heals. And he just got to a point where he was getting better but he couldn't get over the hump."

Sullivan, who last practiced on Aug. 18, was hurt on the field, Zimmer said. Since suffering the injury, Sullivan received two epidurals.

Zimmer said that before the surgery, he expected Sullivan to miss Monday's game against the 49ers. But he was hoping he would return soon.

"We were hoping it wouldn't come to this," Zimmer said. "But it did."

Veteran Joe Berger, whom Zimmer said had been considered as a candidate to start at right guard earlier this summer, now will start at center in Sullivan's absence. Zimmer says he is still not concerned about his line.

"No concern at all," he said. "Just like I said the other day, we expect guys to go in there and play. So they'll do a good job. Berger has played for a long time."

He added: "So actually this all worked out pretty good the way it ended up happening. Harris, he got all the reps at right guard. Berger's been getting all of the reps at center, which is basically his natural position."

Teams are able to place one player per season on IR/designated for return. Those players can return to practice in six weeks and to games after eight weeks. But Zimmer said he doesn't know when Sullivan will be back.

"We've been given a timetable, but that doesn't mean anything," Zimmer said. "We expect him back for the second half."