Now he's seeing if he can fill that void, back at the place where it started for him: in training camp with the Eagles.
No, even with questions remaining about the Birds' secondary, Chip Kelly has not reached to the past for a guy who has not played an NFL snap in two seasons. Sheppard, now 33, is at the NovaCare Complex serving an internship with the Eagles as an assistant coach.
He is hoping the experience and knowledge he gained as a two-time Pro Bowl cornerback can help the current members of the Eagles' secondary prepare for the 2014 season.
"This is something I definitely know and I'm pretty doggone good at," Sheppard said. "It's more than just the X's-and-O's.
"If you can relate to guys and get them to understand that you've been where they are and where they want to get to, you can get the things you are trying to stress across a lot easier. It will start with the fundamentals and techniques, and hopefully I can bring that part to the table."
Like many other former players, Sheppard is using the Bill Walsh Minority Coaching Fellowship to find out if it is a career he might be interested in pursuing now that his playing days are done.
The Walsh Fellowship is one of several programs administered by the NFL Management Council and NFL Player Engagement designed to help players make the transition into the rest of their lives after their playing careers.
The genesis of the fellowship began in 1987 when Walsh, the late Hall of Fame coach, started bringing minority college coaches into his training camps with the San Francisco 49ers to expose them to methods and philosophies.
Shortly after, every team followed the 49ers and ultimately the NFL offices expanded the program to include former players.
The fellowship has guided numerous former players into coaching careers. Cincinnati Bengals coach Marvin Lewis and the Pittsburgh Steelers' Mike Tomlin are graduates of the Walsh program.
Eagles running-backs coach Duce Staley and assistant offensive coach Tra Thomas are former Eagles who turned Walsh internships into full-time positions with the Birds.
"I spoke with [former teammates Staley and Thomas] about the program," Sheppard said. "Tra told me who I needed to talk to with the Eagles to get this process started here.
"Tra and Duce and other former players have been a big help to guys like me who would like an opportunity to try to get back in it."
Get back in it.
For a player to simply make it to the NFL, it generally means that more than 70 percent of his life has revolved around football. If a player is like Sheppard and becomes one of the extreme few who actually has a lengthy career in the NFL, the beginning of his professional life is football.
Is it any wonder that so many players have a difficult time adjusting to a new life when football abruptly ends?
Even after 2 years away from the game, Sheppard concedes that he believes he still could contribute to an NFL roster.
"I did 10 years and I'm proud of my career," he said. "Obviously I felt I had more to give, but it is what it is. It's on to the next chapter."
Sheppard said he believes that coaching football could be that next chapter for him. Not even former players are sure that coaching is the career for them until they've had a taste of it.
A couple of years ago, while Thomas was working on beginning a broadcast career at Comcast SportsNet, he once said he did not think he wanted to coach, even though Andy Reid told him it might be something he would enjoy and be good at.
Thomas impressed Kelly and his staff so much last spring when he started his internship during OTAs and minicamps that he was hired full time before the end of 2013 training camp.
"I would love to," Sheppard, whose internship is scheduled to end Aug. 7, said when asked if he could envision doing this full time, "but that's not up to me. This is a great opportunity for me initially to even get into the internship program.
"After I've played in the NFL, I still feel like I have a lot to offer to the game. My heart and soul has always been in Philly, so if I had the opportunity to come back and help these guys in any way they wanted, I was coming here for my internship.
"Coach Kelly and his staff have an amazing thing going here. I just want to try to add to it in any way that I can to help this team get to that place that we all want to go."