GREEN BAY – Mike McCarthy is keeping the goals pretty simple this weekend.

"We have to get out of the huddle better tomorrow," the Packers' head coach said on Friday, tongue planted at least partially in cheek.

The first practice of rookie orientation at the Don Hutson Center was not the smoothest, but it never is, which McCarthy has come to expect more than a decade into his tenure now.

It was, however, up-tempo and energetic, filled with teaching of fundamentals and how to execute various drills. Those were the priorities, as 55 rookies – seven draft picks, 20 free agents and 28 tryout players – got their first taste of how the Packers conduct business on the field.

There were a few highlight-worthy moments, mostly during one-on-one work between receivers and cornerbacks.

Fifth-round draft pick Trevor Davis hauled in a nice deep ball, and he came back on his next rep to break off the go route and snag another pass on an in-cut. It was a memorable first impression for the speedy Cal receiver.

"You come in really nervous to put your best foot forward and show them what you can do," Davis said. "To have that happen, it helps you get the jitters out, get your legs back underneath you. That was just a really good play for me."

Other highlights included undrafted corner Makinton Dorleant from Northern Iowa jumping a slant route for an interception, and Division III QB Joe Callahan from Wesley displaying a strong arm. Callahan likely will be competing with former Memphis and Miami QB Ryan Williams, a January signee, for a third-string job.

"You can't ignore production," McCarthy said of Callahan, who last year became just the second passer in all of college football to throw for more than 5,000 yards in a season, finishing his career with 130 TD passes. "What we do is different than some things he's done, but anybody that has that much production has definitely earned an opportunity."

That's one thing the Packers emphasize this weekend –every player, whether signed or trying out, was brought in for a reason and has a chance to show something. Southern Oregon receiver Patrick Donahue did his best in that regard, making an acrobatic, leaping catch over a defender while somersaulting to the turf along the sideline.

Tryout players have the toughest road, but the personnel department never stops evaluating prospects, and the roster is always fluid.

"Hopefully they jump out and show you more, and you take that and compare it to other players," McCarthy said. "It's really about creating the most competitive 90-man roster you can."

Off the field, the rookies are learning about the history and tradition of the Packers and getting acclimated to the Lambeau Field facilities.

On the field, the adjustment to the speed of the pro game has now begun, though only six practice-squad holdovers participating this weekend, including 2015 sixth-round draft pick Christian Ringo, had ever participated in an NFL practice before.

For many of the rookies, they were just grateful to be performing football drills after months of training for the scouting combine and pro days. Playbook installation was minimal and basic, but it was enough to leave them ready for more.

"It's nice to have that first practice over, and on to the next one," defensive lineman and fourth-round pick Dean Lowry said. "It's the NFL now, so everything moves faster, and everybody knows their assignment at the highest level.

"It's all football here."

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