When Ryan Mundy was entering his senior year at Michigan, an incoming freshman occasionally crashed on his couch during the summer.

That freshman was a young safety with potential named Stevie Brown.

"Man, Steve just used to always call me when he was about 20 minutes away," Mundy recalled, shaking his head. "I used to be like, 'Dude, you got to give me at least a day's heads-up [before coming over], but he would be like, 'I'm two exits away.'"

That was the summer of 2006. Seven years later, the two are reunited in the New York Giants' secondary. Brown enters this season as a starting safety opposite Antrel Rolle, and Mundy hopes to be the team's third safety.

Ryan Mundy, sporting Kenny Phillips' old uniform number, is in his first Giants training camp. AP Photo/Seth Wenig

After playing five seasons as a backup for the Steelers, Mundy will make his Giants debut in the preseason opener in Pittsburgh on Saturday night.

Mundy, 28, is eager to show what he can do after playing behind Steelers safeties Troy Polamalu and Ryan Clark.

"I am excited," said Mundy, who was born and raised in Pittsburgh. "I thought it was extremely ironic that my first game as a non-Steeler is against the Steelers.

"I had a great opportunity to learn from two of the game's best in Troy and Ryan," Mundy added. "I spent five years under their tutelage and learned as much as I can. This is when it really shows its face, when I get from under their wing and have an opportunity to display what I have learned from them."

In his first summer with the Giants, Mundy has impressed coaches and teammates with his professionalism and play on the field. His transition to a new team and system has been aided by his good friend Brown.

The Giants hope the two former Wolverines will help fill the void left by longtime starter Kenny Phillips, who joined Philadelphia in free agency, and provide a third safety presence for Perry Fewell, who has utilized three safety packages in the past.

"I played with [Phillips] the last three years and we know each other in and out, without even communicating," said Rolle, who spent a lot of the offseason hanging out with Brown to form a bond. "Stevie and I are getting to that point. We are working. We are very versatile right now: We are playing left safety, right safety, strong safety, free safety. It doesn't matter what it is, we are just jelling."

"Mundy is a true professional," Rolle added. "He takes his game very seriously on and off the field. We are all pretty much on the same level and we are all making plays."

Rolle says Brown is much more comfortable in his second season with the Giants. Last year, Brown was just trying to make the team. He went on to be the surprise of the season, collecting a team-high eight interceptions and returning them for 307 yards.

Brown, 26, hopes that feeling more comfortable and knowing the defense will lead to even better results.

"This is the first time I have been in the same system since my sophomore year in college and had the same D-coordinator since my sophomore year at Michigan," said Brown, who played for Oakland in 2010 and Indianapolis in 2011 before joining the Giants last year. "So it definitely brings a lot of comfort level to me. I already know what happened last year and I can learn the little things this year."

Mundy has immersed himself into the Giants' defensive playbook. He is meticulous about his approach, almost in a Coughlin-like manner.

"Mundy has a more militant style of approaching the game," Rolle says. "Doesn't want to make a mistake, wants to know the ins and outs of the defense, being that this is a new system for him. He is doing a great job so far."

Last year, Brown capitalized with his first major opportunity as a starter. Now Mundy wants to show what he can do if given the chance.

And Mundy will do it with the support of a guy who once used to look to him for a couch to crash on.

"Things come full circle," Mundy said. "And we are teammates again."