The five-time league MVP refused to talk about just why he was carrying the bright green, lycra-covered ball after the practice.
"That's Denver Broncos offensive business," he said.
When asked if it had anything to do with the green football Demaryius Thomas carried for the entire 2012 season -- after a series of fumbles -- he again declined to explain.
"Like I said, that's official Denver Broncos offensive business, right? It's kind of an A and B conversation and you can C your way out of it," Manning said.
The Broncos as a whole had a bit of a ball control issue last season with 27 fumbles, six of which Manning was responsible for.