Vikings notes: Sullivan's concussion was his fifth

Center John Sullivan says he is fully recovered from the concussion he suffered in last weekend's loss to the Buffalo Bills and expects to start for the Vikings on Sunday against the Tampa Bay Buccaneers.

In his first public comments since he was concussed, the veteran was candid about his history of concussions and the internal debate that players go through when these injuries occur.

Sullivan was kneed in the head during a first-quarter running play. He went straight to the bench, and after the symptoms initially subsided, he got in an argument with head athletic trainer Eric Sugarman because Sugarman wanted him to undergo more tests before returning to the game.

On his way to the locker room, Sullivan suffered another spell of dizziness, and after further examination the determination was made to hold him out of the rest of the game.

"It was not a catastrophic hit by any means," Sullivan said. "In order to go back into the game, I was going to have to lie to our doctors and to the [independent] neurologist, and I wasn't going to do that."

Sullivan, who has suffered five known concussions in his life, is aware of the impact that concussions have made on the long-term health of many former players. But he said it can be hard for a player to think about his health first when he is caught up in the heat of the moment and wants to play.

"As players, it's tough, because you don't want to tell a guy how to live his life. But we have a responsibility to be honest about what we're going through with those hits," Sullivan said. "You feel like you have a duty to yourself and your health and your family to tell the truth. But at the same time, even though you are suffering symptoms, you feel like you're letting your teammates down."

Asked what his role might be against the Buccaneers, the veteran lineman played coy.

"I may or may not know that," said Berger, who has been with Vikings since signing as a free agent in 2011. "If you guys don't know that, I'm going to let the coach tell you guys that."

Head coach Mike Zimmer wasn't candid either when asked if Berger might start.

"I don't know," he said. "We'll see. [Right guard] Vlad [Ducasse] practiced today, so we'll see."

Ducasse is listed as questionable because of a knee injury, but practiced fully Thursday and Friday.

The injury happened during individual drills at the start of Thursday's practice. Robinson wasn't going full speed when he rolled his ankle, which he hopes will help with the recovery process. He said his ankle was feeling better Friday and was optimistic about playing.

"It got rolled up a little bit [Thursday] in individuals but … it's not too bad," he said.

Rookie cornerback Jabari Price would likely replace Robinson in the nickel if he is sidelined.

Rookie safety Antone Exum (ankle) was also listed as questionable. Outside linebacker Gerald Hodges (hamstring) is doubtful despite practicing on a limited basis the past two days.

Defensive tackle Tom Johnson, who signed as a free agent in the offseason, has proved to be a valuable contributor on passing downs. The reserve ranks second on the team with four sacks.