Denver Broncos quarterback Peyton Manning declined to explain why he carried a green football on Wednesday during the team’s first day of Organized Team Activities (OTAs), but his head coach wasn't quite so secretive.

Manning’s green football, which is really just a normal football covered in green Lycra, stirred speculation during the Broncos’ post-workout news conference. Despite the interest in the prop, the 2013 NFL MVP was evasive regarding the reasons he was carrying it around the team‘s practice facility in Englewood, Colorado.

“That’s Denver Broncos offensive business,” he said at the start of the news conference, according to USA Today.

But Manning wasn’t the only member of the Broncos spotted with a green football. Demaryius Thomas, the team’s top wide receiver and recipient of 14 of Manning’s record-setting 55 touchdown passes last season, was also seen carrying a green football.

In 2012, the Broncos coaching staff required Thomas to carry a green football after he lost fumbles in back-to-back games, USA Today notes. Given that history, reporters asked Manning if the green footballs at 2014 OTA’s were meant to serve a similar purpose.

“Like I said, that’s official Denver Broncos offensive business, right?” Manning said in a playful rebuke to reporters. “It’s kind of an A and B conversation and you can C your way out of it.”

But Broncos head coach John Fox gave up the secret, telling reporters that ball security was one of his chief concerns in 2014. "We're making an emphasis from Day 1 on ball security," Fox said, via the Denver Post. "We started with two of our better players in Demaryius and Peyton. What better guys to start with?"

Manning may not have been willing to confirm that the team was working on its ball security issues, but a look at Denver’s stats in 2013 shows that fumbles were a serious issue. The Broncos fumbled the ball 26 times last season, 16 of which resulted in turnovers. Furthermore, Manning himself accounted for six of those lost fumbles as well as an additional one in the team’s Super Bowl XLVIII loss to the Seattle Seahawks.

Broncos offensive coordinator Adam Gase addressed the problem in a news conference last week. “Guys really hurry themselves, then all of a sudden they get a little lackadaisical with the ball,” he said. “We have to do a better job as a group with that. That was a big downfall for us early, where the ball was on the ground way too much. It’s almost two seasons in a row and we have to address that right away. We’ve got to be so much better as far as holding onto the ball as a group.”