"I want to retire as a Giant," Grant said in a team release. "Because I want to be a Giant for the rest of my life."
The safety has not played since the Giants won Super Bowl XLVI over New England. He underwent surgeries on his shoulder, ankle and hand and did not play in 2012.
"The Giants are a connection in my heart that I knew that I was supposed to be there," Grant said. "The last year that I signed there to go to the Super Bowl, I could have signed with a bunch of teams, but I wanted to sign with the Giants.
"The way that the owners opened the doors and signed me back and the general manager [Jerry Reese] and the coaching staff ... we did each other a favor, but it definitely solidified my career for me."
Grant was the Carolina Panthers' second-round draft pick in 2000. The safety played for the Panthers, Jacksonville Jaguars and Seattle Seahawks and started all 144 regular-season and seven postseason games in nine seasons at one point in his career. He signed with the Giants in 2010 and played in 36 games in two seasons, including playoffs.
"I understood the game a lot more at that stage," Grant said. "When I went to the Super Bowl in Carolina [in 2003], I was so young I was really -- I'm not going to say [not] taking it serious, but I was battling a hip injury, a [potential] career-ending injury, and every year that went by I was just trying to last another year."
"But once I got to the point that I was at when I got to the Giants, I was a lot more comfortable," he continued. "I knew how to enjoy the game instead of just taking it play by play or day by day. I really knew what to look forward to, and I knew what my main focus and my main goal was."
Giants coach Tom Coughlin raved about Grant's intelligence and versatility as a player.
"He did a great job when he was here," Coughlin said. "Mr. Versatility. Played (some) linebacker (as a third safety), played back in the secondary. We had a package basically designed to get him and others on the field at the same time and he responded very well.
"Very smart player," he continued. "A guy who can direct traffic, the guys respected him. He had an ability to recognize when things weren't championship quality. Guys respected him for that. I look forward to seeing Deon again and see if we can get him in here and talk to the team."