GREEN BAY – The realization hit Sam Barrington as soon as the Packers’ fourth-year linebacker woke up on Tuesday morning.

The day is finally here.

After an almost one-year hiatus, Barrington was given the green light to return to the practice field on Tuesday night for his first on-field action since sustaining a season-ending foot injury in the 2015 regular-season opener in Chicago.

It felt almost like the first day of school for Barrington – a blend of excitement and anticipation after a lengthy layoff from the game he’s played for the past 20 years.

Barrington would be lying if he said he didn’t feel a few nerves, too.

“I was like, ‘Darn, do I know how to play football still?’” joked Barrington.

Those questions quickly were answered once he stepped back on the field. Known for his physicality, the linebacker’s willingness to hit could be heard in his first half-line drill.

Also noticeable were the changes Barrington made to his body this summer. He’s down about 10 pounds from the weight he played at last season and more than 20 since December.

Due to the nature of his foot injury, Barrington was off his feet for the first few months of his rehab, causing his weight to jump from 247 pounds in the opener to around 258.

Over the next eight months, Barrington made a series of changes to his diet and worked tirelessly to put better weight on his 6-foot-1 frame in time for the start of the season.

So far, Barrington can feel a difference on the field.

“I just look like a rock, but I definitely lost weight and built more muscle,” said Barrington, laughing. “That’s probably been the big difference because I can move different, I’m able to shift my weight different. I didn’t lose any strength. I just lost the weight. Dropped my body fat. Last year my playing weight was about eight pounds heavier than it’s going to be this year.”

After a promising finish to the 2014 season, Barrington was positioned to have a significant role in the defense last year before the foot injury in Chicago.

Instead of breaking through, Barrington was forced to step back. His absence had a domino effect on a defense that then cycled through Clay Matthews, Nate Palmer, Jake Ryan and Joe Thomas at inside linebacker last season.

Now that he’s back, Barrington hopes to reinstall his brand of aggressiveness to the defense. He doesn’t know what role awaits him, but he’s ready for anything.

After having to scramble to replace Barrington last year, count defensive coordinator Dom Capers among those happy to see the linebacker back on the field.

 “It was good to see him back out here,” Capers said. “No matter how much you work off to the side, it’s getting out there and playing football, but I think it’s a good start for Sam. We just have to keep progressing him in terms of the reps he gets. The key is keeping him out on the field.”

Barrington stayed in Green Bay during the year and embraced a leadership role at a young position. It helped him stay sharp with the defense and not get discouraged.

In his first two practices back, Barrington already has enjoyed working with Blake Martinez, lauding the rookie fourth-round pick for his leadership and communication skills.

He doesn’t view Martinez or any of the young linebackers in the room as competition or threats. Barrington’s mentality is shaped more by what he’s doing than those around him.

“I don’t care if I had three teddy bears backing me on the depth chart, I’m going to work hard. That’s how I am,” Barrington said. “Hard work has always been in my lunch box. It doesn’t matter who I’m playing against. It doesn’t matter who I’m playing with. I’m going to work hard regardless.”

Equipped with fresh legs, Barrington mentioned how a few teammates even told him to “calm down” a little in his first practice back.

You’ll have to excuse Barrington. He’s had a lot of pent-up aggression these past 11 months.

 “Being physical, that’s going to be there,” Barrington said. “That’s who I am. No big deal. But defense needs a lot more than physicality. We need continued leadership. We need emotional endurance. We need emotional intelligence.”

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