The Vikings have signed Chris Crocker, adding another man to the unsettled safety position group.

Crocker has played seven seasons under Vikings head coach Mike Zimmer. He was with Zimmer in Atlanta in 2007 and joined him a season later in Cincinnati, where he played his last six seasons. In 2012 and 2013, Zimmer talked Crocker out of semi-retirement to bail out his Bengals secondary.

Now, with one of the safety positions here wide open, Zimmer has called on the 34-year-old again.

"You are always kind of ready, especially when you have a guy like Zim that you can play for," Crocker said. "We have a rapport and we talk often. At this point in my career, I really didn't want to go anywhere else. I'm not starting over. I wanted to come here and play for a guy who has meant a lot to my career. I've given him everything I have. Just empty the gas tank and see where it goes."

The safety position next to Harrison Smith has been in flux since the start of spring workouts. Jamarca Sanford, a starter in 2012 and 2013, missed most of the spring, as did Andrew Sendejo, who returned from the PUP list earlier today and is about to take place in his first practice of the Zimmer era. Robert Blanton is out with a hamstring injury after opening camp with the first team.

"[Zimmer] said I could help these guys get better and also come in as a playmaker," Crocker said.

Crocker, at the very least, is familiar with Zimmer's system. He started three games for the Bengals in 2013 and nine the previous season. In total, he has started 70 games in seven years with Zimmer.

"I've been in this scheme pretty much my whole career," Crocker said. "Just to come in, it's the same terminology and I know most of the staff. I played with and against a lot of these guys, so I have a lot of familiarity. Zim is the ultimate [defensive backs] coach. So I take my lead from him. It shouldn't be tough. Obviously, I know the scheme and I'll help these guys learn it also."

Overall, Crocker has recorded 554 tackles, 14.5 sacks, 60 passes defended and 15 interceptions in 151 games over 11 NFL seasons with four teams. He started his career with the Browns in 2003.

To make room on the 90-man roster, the Vikings have released rookie defensive end Rakim Cox.