GREEN BAY, Wis. -- Aaron Rodgers has long believed in the importance of players' spending extra time in their playbooks, especially guys who are new to the Green Bay Packers’ offensive system.

This offseason, the Packers quarterback is having to practice what he preaches, thanks to changes head coach Mike McCarthy has made.

“You really have to fit a lot of stuff into a short amount of time [during the offseason], so it puts extra pressure on the coaches to be able to go through that plan with the young guys and then get them up to speed. It puts a strong onus on them to spend time away from the facility studying their playbook -- myself too,” Rodgers said during a break in the team’s organized team activity practices.

“There’s some changes this year, so I’ve had to put in some extra time in the offseason, which is a little rare, to make sure I’m good on the way we’re calling personnel now and some of the plays we’ve changed.”

Aaron Rodgers knows Mike McCarthy's system very well, but even the veteran QB has some things to learn in the Packers' recently updated playbook. Harry How/Getty Images

Added wide receiver Randall Cobb: “It definitely is important to keep things fresh. Not only do we have little new things, but we have little new ways of calling things in the playbook. So we’re kind of relearning the playbook in a different sense this year.”

Neither Rodgers nor McCarthy wanted to divulge too many specifics about the changes, and McCarthy called them “big picture” changes.

But after more than a decade in McCarthy’s offense, the changes are obviously significant to require Rodgers to devote extra study time to them. It sounds as if McCarthy’s changes are intended to simplify the language of play calls.

“As far as Aaron, I don’t want to change anything, unless it feels really important. You don’t want to change just to change, especially if it’s going to affect your quarterback, especially Aaron Rodgers,” McCarthy said. “So the changes are for a reason. He clearly understands it. He clearly sees the big picture benefits of it. So, it’s something that everybody’s had to adjust to.”

That’s somewhat uncharted territory for Rodgers, who spent his rookie year in 2005 in Mike Sherman’s offense and has been in McCarthy’s system ever since, including eight seasons as the Packers’ starter. Although McCarthy’s scheme has evolved over the years, and he has tailored aspects of the offense to Rodgers’ skill set after two years with Brett Favre at the controls, this is a bigger change than in past years.

“The beauty of being in one system for your whole career is obviously stability. And you’re winning. The greatest quarterbacks out there have all played in the [same] system for a long time,” said quarterbacks coach Alex Van Pelt, who spent nine years with the Buffalo Bills, under three head coaches and five offensive coordinators. “That’s also a detriment when you do make changes.

“For a guy that’s been three years here, four years there and two years here, it’s easier to shift those gears and just forget and relearn. Whereas, you’ve got a lot of history in certain things that are called, and for a player who’s been in the system the whole time, it’s difficult.”

At the same time, Van Pelt said, the changes are a good change for Rodgers.

“It does challenge him. It makes him dive back into the playbook and learn some of the new verbiage that we’re using," he said. “[The new language] cleans it up, makes it easier for the younger guys that are coming in, so it’s a give-and-take. But he definitely had to throw himself into the book a little more this year.”