GREEN BAY – Aaron Rodgers was in the business of making changes this offseason.

After what could be considered a down season for the two-time MVP, the Packers quarterback adopted a vegan-like diet, cutting out dairy and eating meat more selectively.

Rodgers told reporters during the offseason program that he weighs about 218 pounds, the lightest he’s been since 2007.

On the team’s first day back for training camp, Packers Head Coach Mike McCarthy has taken notice of the alterations Rodgers made.

 “I would say Aaron’s vibe and really his offseason participation and performance looks to line up for a great year,” said McCarthy during his opening training camp news conference on Monday morning.

“He’s in great shape. I would say this is the best shape I’ve seen him in.”

By most accounts, Rodgers had a fine 2015 season that saw him throw for more than 3,800 yards with 31 TDs and only eight INTs. It all culminated in his fifth Pro Bowl selection.

Still, the offense didn’t operate on the same plane that it has grown accustomed to.

 In the aftermath of Jordy Nelson’s season-ending knee injury, the Packers fell from sixth to 23rd in total offense, while Rodgers’ 92.7 passer rating was the lowest of his eight years as starting quarterback.

McCarthy admits the setbacks forced the coaching staff to take a long, hard look in the mirror after the season, taking the first three months of the offseason for scheme evaluation.

The Packers’ diagnosis was the fundamentals weren’t where they needed to be. The offensive coaches are using that as a strong point of emphasis in the installation process in camp.

“We need to be much better offensively in the area of fundamentals,” McCarthy said. “Last year was not good enough and the numbers reflected that. We clearly addressed that. We had a chance to go back and view all the cut-ups. Those cut-ups and lessons learned will be part of our installation phase during training camp.

“But we need to improve on a number of things fundamentally and that’s what training camp is for.”

McCarthy acknowledged the Packers likely won’t have all their installations in prior to the Pro Football Hall of Fame game against Indianapolis, but the extra week of camp and five preseason games should help with cross-training the offense and defense.

One area where McCarthy isn’t concerned is redeveloping the chemistry between Rodgers and Nelson, whose rehab stretched into most of the offseason program.

McCarthy wouldn’t go into specifics about Nelson’s progress, but he isn’t worried about how the Pro Bowl receiver will transition back into the offense.

In their most recent season together, Rodgers and Nelson were catalysts for an offense that led the league in scoring (30.4 points per game) in 2014.

In the process of Rodgers notching an MVP, Nelson and receiver Randall Cobb became the first duo in NFL history to both register 90-plus catches, 1,200-plus yards and 12-plus TDs in a single season.

“I think we’re all confident, Aaron and Jordy included, that they’re going to get (the chemistry) back,” McCarthy said.

“It’s just a matter of getting back out on the field and getting the reps. You’re talking about two players who have thousands of reps invested in their time together. I have great confidence they’ll get that back.”

The Packers hit the field for their first training camp practice at 8:15 a.m. on Tuesday. Like every year, the goal remains the same.

“It’s about winning a world championship,” McCarthy said. “It’s a part of our every-down fiber here in Green Bay. Every team in the National Football League, I’m sure, is talking about that their first day of training camp.”

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