"That's my buddy," Johnson said of Sharper. "He taught me a lot of things when he was here. Good friend of mine. I hate to see him go, but that's the nature of the business."
With Sharper's departure comes an opportunity for Johnson, the Vikings' second-round draft pick last year.
"I'm very fortunate and very blessed to be in the position that I'm in, to compete for the starting role, and I'm going to go out there and do my best," he said.
Johnson started the first seven games of his rookie season after free-agent signee Madieu Williams suffered a neck injury in training camp. That experience last year likely will help Johnson this year.
"He learned how to play football at this level. He realized that the preparation has to be different than it was in college," Williams said. "There is a lot of ownership on you individually to make sure that you prepare and get yourself ready to play on a week-to-week basis. There is not a lot of emphasis on people telling you what you have to do. It's your job and the ownership is on yourself to go out and make sure you're ready and you go out and execute on Sundays."
During his first seven games, Johnson registered 29 tackles, one fumble recovery and one interception in Williams' stead. He also had five tackles in the playoff loss to Philadelphia.
"It helps him out a lot in terms of playing experience, those things are invaluable," Williams said. "You can't replicate that in practice. For him to get that learning curve out of the way early will serve huge for him later on in the season."
Johnson said he learned from Sharper's veteran experience.
"When you're playing with a veteran like that, you kind of pick up on his composure. As the game goes on and situations get tough, he was probably the most composed individual that I've seen out there. Watching him and playing with him I think I picked up on a lot of his composure," Johnson said.
While he had plenty to learn about the game at the professional level, Johnson certainly had the talent before he ever signed his first pro contract and became the team's only draft pick in the first three rounds last year. One of his fellow rookie safeties was well aware of Johnson's physical talents before he ever donned a purple jersey.
"Tyrell is a beast," said Husain Abdullah, who made the team last year as an undrafted rookie. "He was a beast at the (NFL Scouting) Combine. Last year, Madieu went down and so you've got to step in and you've got to start. He started half the year and did a great job. Then, after that, when he came back, they said, ‘Now you've got to go special teams.' It was a transition in the middle of the season, but then he went on special teams and he started balling on special teams. Tyrell is a helluva football player."
This year, Johnson is expected to get more of an opportunity to show that talent on a consistent basis in 2009.
"I'm pretty much doing everything. I'm modified in a few exercises, but for the most part it's everything," he said. "There's a lot of rust there. I missed the whole season so I'm shaking it off.
Mitchell wasn't tendered as a restricted free agent, but he did sign a two-year contract with the Vikings and is anticipating his comeback season.
"I can't wait to get back out there. It really hurt me when I injured myself. I love being out here. This is my element," Mitchell said.