NASHVILLE, Tenn. –* *Michael Griffin didn't know how long he'd play in the National Football League when he first walked in the front door at Saint Thomas Sports Park.

A first-round pick of the Titans in 2007, he was taking in "day by day."

"The main objective was to get through that rookie camp, and then that rookie year," Griffin said on Monday. "You look around, and some guys don't make it, don't pan out. Of course you want to have a long career, but it's hard. Nothing is guaranteed."

Griffin officially retired from the NFL on Monday. He signed a one-day contract to retire a Tennessee Titan, where he played nine seasons. Griffin stood inside the team's indoor practice facility answering questions about his career, and before walking out the revolving door, his wife and three children behind him, he said he felt blessed.

Four of his former teammates – linebackers Brian Orakpo and Wesley Woodyard, and defensive linemen Jurrell Casey and DaQuan Jones – showed up for the ceremony and exchanged handshakes and hugs one final time inside the Titans fireball logo.

"To be able to walk away from the game after so many years," Griffin said, "I feel very blessed. When I look back at my career, I have a lot to be thankful for I know. … To play nine years (in Tennessee), that is sometimes unheard of. … This is a special day for me for sure. I always wanted to retire a Titan."

Griffin played from 2007-2015 in Tennessee. He was twice named to the Pro Bowl, and he played in 141 career games for the team, including 103 consecutive games between 2007 and 2013.

Griffin is the franchise's all-time leader in tackles by a safety with 912. In his Titans career, he tallied 25 interceptions, seven sacks, 11 forced fumbles and six fumble recoveries. Griffin recorded seven interceptions during the 2008 season. He played his final NFL season with the Panthers in 2016.

On Monday, Griffin thanked the fans and his teammates for the memories, and the Adams family for giving him a chance. Titans controlling owner Amy Adams Strunk talked to Griffin on the phone on Monday, and Titans general manager Jon Robinson and coach Mike Vrabel spent tiime with Griffin when he was in the building.

Griffin said he wanted to close the chapter of his life with the Titans, and officially begin his life after football. He admitted he still misses the camaraderie of being around his teammates.

Griffin was joined by his wife Shantel, and his three children – son Braylen (9), and daughters Mya (7) and Mikenzie (13 months). They followed him around the building, watched him sign his contract, and looked on as he answered questions about his career. The youngest bounced around the field as Griffin caught up with old friends.

During Griffin's playing days, his family was just getting started. Now, many of his former teammates, from Keith Bulluck to Cortland Finnegan to Chris Hope are getting used to retirement as well.

"I mean, it lets you know how old we really are. You see right here, I have all this gray and stuff in the beard," said Griffin, 33, smiling.

Griffin's kids are keeping him busy these days, along with Gigi's Cupcakes in Austin, Texas -- Griffin opened a store with Orakpo, his former college teammate at Texas, last fall. He also went back to school to get his degree.

He's keeping himself in good shape, and is playing in the American Flag Football League – his first game is July 7 in Atlanta.

"My football career is not technically over," he said, smiling again.

His NFL career officially ended on Monday, however. When asked what advice he'd give today's rookies, Griffin said "soak it all in."

Griffin, who didn't play last season, admits he still misses the game.

But he's thankful for the years he had in the NFL, and the memories.

"It was tough (last year)," Griffin said. "There were some days where you'd wake up, especially Sundays, and … when kickoff came at 12 o'clock I would try and occupy myself, go play basketball or something to get my mind going. "But when you start looking back at it, you kind of look at yourself being selfish when you are saying you played 10 years and you want to pout about it or be upset about not being able to continue to play. Again, there's some guys who go through that rookie minicamp and training camp and don't ever get to play a down of football after college. I have a twin brother who never played after college.

"I started thinking more and more, having my family there, my wife and kids, and being able to go to their games and things of that nature. I really started seeing there is life after football," Griffin continued. "It was tough at first, but right now I am at ease. I get to retire a Tennessee Titan. This is where I started at, and now you close that chapter in my book and it's time to start a new chapter."