PITTSBURGH -- One item was clearly out of place in the Pittsburgh Steelers' locker room on the final day of minicamp.

But Mike Mitchell said there was nothing to read into the Carolina Panthers helmet hanging in his locker on Thursday.

"It means I haven't found a house yet to put it in my basement," Mitchell said.

Mike Mitchell is working on building a rapport with his new teammates. AP Photo/Keith Srakocic

The Panthers mailed Mitchell a helmet that many of his former teammates had signed, and there is some significance to the keepsake from the season he spent in Carolina.

"That group that we had there last year I think the biggest thing that made us so successful is we were genuinely friends off the field and really cared about each other," Mitchell said.

The Steelers' defensive players have generally been a tight group and that bodes well for the transition Mitchell is making on the field and away from it.

Mitchell becomes just the third free safety to play regularly with Troy Polamalu, joining Chris Hope and Ryan Clark, and the two started to get to know one another during minicamp.

"He's a super nice guy," Mitchell said. "It's humbling for me to see that because for him to be one of the best safeties to play the game he's a super humble guy. The way he treats people and goes about his business I admire that a lot. It's not even a football thing it's a personal thing I've noticed."

Much has been made about the rapport Polamalu and Clark developed and how much it helped the two on the field.

There is no reason to think that Polamalu and Mitchell won't build a similar friendship.

Polamalu is a super nice guy when he is not chasing down running backs as if they stole something from him or soaring over the line of scrimmage and landing in the laps of startled quarterbacks. The eight-time Pro Bowler is one of the biggest pranksters in the Steelers' locker room, something that also endears him to teammates.

Mitchell, meanwhile, is an engaging guy who wants to be great and relishes the opportunity to play with a safety of Polamalu's caliber. He is, in fact, a lot like Clark though with the volume turned down.

"What made Chris Hope and I very successful on the back end is that we were great friends. The same thing with Ryan," Polamalu said. "With any other team, it's just plug-and-play. But the strength of this organization has always been in the camaraderie and the relationships of the players off the field, and then we stand up for one another on the field. So we have to develop those relationships."

It will be a process with Polamalu and Mitchell and one that really starts when the Steelers report to training camp on July 25th. But Mitchell is confident that he and Polamalu will get to know one another well enough for them to thrive together on the field.

"It's just us hammering out reps together," Mitchell said. "I think you need a little adversity too because you can't really tell who a person is or how they're going to respond until you get into tough situations. It could be a game until we really are on the same page now but it's a process of growing together so we can get to a point where I just know how thinks."