Staley, who turns 38 on Feb. 27, has clearly been bitten by the NFL coaching bug after 10 seasons as a running back, including his first seven with the Eagles.
As for coaching, it wasn't something he originally thought would be something he'd pursue.
"I would hear horror stories about how you might as well get a couch in the office and sleep there three to four days a week," Staley said with a laugh.
Still, in two years Staley has become consumed with coaching, and Williams has been proud of the way his former running back has adapted to his new profession.
"He is a student of the game and has a very strong passion for football," Williams said. "Duce has a strong work ethic and is prepared to work that extra mile."
When Reid hired Staley, he said he had a project for him.
"The project was LeSean McCoy," Staley said. "I was able to spend time with him and get on the same page with him and show him how I did it."
In Staley's first season as coach in 2011, McCoy rushed for 1,309 yards and scored a team-record 20 touchdowns, including 17 on the ground, while earning his first Pro Bowl berth.
This past season, McCoy suffered a concussion and missed four games, rushing for 840 yards and two touchdowns. Now Staley is looking for a return to the 2011 level for the Eagles' top running back.
"When you look at the kid, he can be a special back every down," Staley said.
When asked if he would give McCoy any advice regarding matters off the field in light of the running back's recent Twitter feud with the mother of his son, Staley said his main priority is football-related.
"Off the field is not my area," he said. "I will give him advice if he asks, but my job is making sure LeSean is the best he can be on the field, along with the other running backs."
As a player, Staley was a fan favorite during his tenure with the Eagles from 1997 to 2003. As an Eagle, he rushed for 4,807 yards, fourth most in team history. He was voted team offensive MVP three times - 1998, 1999, and 2002.
Staley spent his last three seasons in Pittsburgh, often battling injury. He was a member of the 2005 Steelers team that won the Super Bowl.
"In Duce, I've got a guy that's not only won a Super Bowl but been in Philadelphia - tough, hardnosed, intelligent," Kelly said. "You're around Duce for 20 seconds, and you know a guy that just absolutely loves football. So it was important to have that around."
Staley said it's even more special to remain with the Eagles and be able to work with the running backs on a full-time basis.
"It's a great feeling to coach the position I played," Staley said. "It's important to have a great relationship with our running backs and take what I know and what was taught by Ted and pass it on."
See Eagles running backs coach Duce Staley talk about the team's toughness at philly.com/eaglesvideos
Contact Marc Narducci at email@example.com. Follow on Twitter @sjnard.