McCoy, who beat the Minnesota Vikings' star for the NFL rushing title last season, believes himself the most complete back in the league. That led to a media back-and-forth with Peterson last month, which started when McCoy told ESPN he was the NFL's best back.
"I don't know how people may take that," McCoy said after Monday's practice session. "It was a question I was just being honest about. I can't worry about how other people think about it. That's why we work every day. That's why I try to perfect my game. So that if people want to prove me wrong, they can."
Peterson said on the radio McCoy was just kidding, and said he advises young players to speak up when they're serious.
"It was funny because ... he kind of hesitated, and he didn't believe it when he said it," Peterson said. "I tell the youngsters, 'Say it with your chest, like you mean it!'"
McCoy found that response confusing.
"I don't know him that well," McCoy said. "I don't know if he's joking or what. I play the game. It speaks for itself. I don't know what that meant. I don't know if that was joking. He was saying a lot. I don't know what that meant."
At a time when the running back position seems to be evolving -- with more emphasis on catching passes and blocking than running the ball -- the Eagles were committed to running it under first-year head coach Chip Kelly in 2013. And that was a huge change from the pass-first, pass-second philosophy of former coach Andy Reid.
"Coach Kelly, he just wants to win," McCoy said. "If it's running the ball a million times or passing it, he's going to do it. He doesn't have that pass, pass, pass or run, run, run thing. Whatever's working, that's what he's going to do."
When McCoy finished the season finale in Dallas with a firm grasp of the NFL rushing title, he donned a boxing-style championship belt to celebrate. He is not reluctant to show his confidence. But it is the other parts of his game -- blocking, running routes -- that he feels give him the edge over Peterson or anyone else.
"You look at the tape," McCoy said. "As a back, I do everything -- running, blocking, as a third-down back in and out. There's nothing that I can't do. The last three years, I don't feel there's a back who's more productive."
He couldn't resist throwing another shot Peterson's way.
"Ask my man in Minnesota," McCoy said. "Check the numbers. Especially the last two years, to be sure. Check those numbers."