GREEN BAY—After months of preparing to run 40-yard dashes, dodge in and out of cones, jump as high as possible and bench press to the point of exhaustion, the Packers' rookies couldn't have been more thrilled on Friday to finally do what they've been training to do.

Play some football.

"It felt great," linebacker and fourth-round draft pick Carl Bradford said following the first of two rookie workouts this weekend at the Don Hutson Center. "I haven't had a football practice since December. It had been months since I got out there. It felt amazing to get in football mode instead of testing mode."

The players went through roughly two hours of drills and got a fair share of seven-on-seven and 11-on-11 work thrown in. That's the stuff football players miss most, competing against the guy lining up on the other side.

The pads won't go on until training camp in late July, but putting on an NFL jersey and helmet for the first time was still a pretty special moment – one that combines graduation and orientation for players who have dreamed to get to this point.

"It's like the first day of school," safety and first-round pick Ha Ha Clinton-Dix said. "It's starting over from the bottom again, trying to learn the plays, trying to get out there and have fun and play fast."

Sometimes too fast. A handful of center-quarterback exchanges were botched, with the ball ending up on the ground, but that's to be expected. So were the ups and downs experienced by many.

Receiver Jared Abbrederis looked as smooth as could be fielding punts from the Jugs machine, but he slipped on an in cut as a quick pass nearly drilled him in the head.

Fellow receiver Davante Adams dropped an easy throw on a hook route but shortly thereafter neatly snagged a slant.

Cornerback Demetri Goodson was outjumped once but later ran step-for-step down the sideline with receiver Jeff Janis to break up a deep ball.

Good and bad, the game was on again.

"It's a sigh of relief," third-round pick and defensive lineman Khyri Thornton said. "The football field is my sanctuary. You can't let out aggression anywhere else except the football field, so when I'm out there, I forget everything. It's my comfort zone."

Less comfortable is trying to learn an NFL playbook for the first time, but it's a high priority. To a man, every draft pick interviewed after the workout said getting the playbook down – and only a small fraction is being revealed this weekend – was his primary goal.

"That's the most important thing," Clinton-Dix said. "My nose is in it 24-7. I'm trying to pick it up as quick as possible. The more I know, the more respect I'll get."

Center and fifth-round pick Corey Linsley said knowing the plays is the only way to be able to go 100 percent every snap and not be "slow and timid."

Different players come from different college systems. In Fresno State's spread offense, Adams said the receivers just looked at quarterback Derek Carr at the line of scrimmage, and everyone knew what to do. It's not that simple anymore.

"You have to know everything at the beginning, (but) make one check and you have to know a whole new play," Adams said.

Some of the rookies arrived in Green Bay early in the week and have already had a chance to meet a few veteran players and do some position drills with them as part of the offseason program.

Bradford said that's when it hit him it's all for real, while chatting with Clay Matthews and A.J. Hawk, who welcomed him to the team the way only pro athletes do.

"Congratulations on being here and get ready to work," Bradford said they told him. "There's no more babysitting, no more room for mess-ups."

That's as good a reality check as any. Friday was only the beginning.

"Growing up a Packers fan, it's an amazing feeling to put on the helmet," Linsley said. "But I actually have to earn it and make the roster to call myself a Packer and consider myself a teammate of these guys, so I've got a long way to go." Additional coverage - Rookie orientation

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• Press conference & locker room videos