JACKSONVILLE – The roster was shorter, and the locker room had more space. A lot more.

Notable, too, were the wide smiles of young players – that and the intensity of pretty much every player in the Jaguars' locker room or on the practice field.

This was Regular Season Monday No. 1, and for nearly every NFL player, it's a day that brings perspective along with a bit of the aforementioned ramped-up intensity. It's a day closer to the real deal and it absolutely feels that way.

And for some rookies – particularly a few long shots – the day is flat-out a dream come true.

Two days before, one of those long shots – linebacker Thurston Armbrister from the University of Miami – waited much of the day to learn if he had made the team. Late that afternoon, linebackers coach Robert Saleh called with the news.

The thrill hadn't yet faded on Monday.

"Man, It was a moment of relief," Armbrister said with a smile. "Now, it was about finding what my role was going to be and accepting it. Now, I've got to move forward."

Cornerback Nick Marshall spent Saturday with his mother and learned he had made the team via Twitter.

"It was a great feeling for us," Marshall said. "It was a cool moment because it was something I always dreamed of as a kid. I was just thrilled to be a part of the Jaguars."

Armbrister, Corey Grant and Marshall – those are the three players who made the 53-man roster as collegiate free agents. That means overcoming varying odds, but they were far from the only players on Regular Season Monday No. 1 with smiles, or with a perspective on what it means to be in the NFL.

When players dress for practice on Regular Season Monday No. 1, they do so next to empty lockers that days before housed competitors, friends. Practice is a more intimate setting, too. No more reserves deep on the depth chart to get reps.

The 63-man NFL environment of the regular season – active roster plus practice squad – is dramatically different than the 90-man feel of the offseason or even the 75-man feel of a week before.

Players undoubtedly feel it. The perspective felt Monday is real.

"I was just thinking that, looking at the roster – there aren't that many guys who make it," five-year veteran center Stefen Wisniewski said. "There are only a few at each position and it's definitely an elite fraternity to be a part of, guys who make a roster. It's even tougher to make it several years in. It's definitely a special thing. I feel blessed."

Underlying all of that, of course, is the fact that Regular Season Monday No. 1 clearly means this:

The real thing is just six days away.

And while players and coaches know this all along – and while they even began some preparations for Sunday's game against the Carolina Panthers around last Thursday's preseason finale at Washington – there unquestionably is something different this week.

The pace to practice …

The energy …

Jaguars Head Coach Gus Bradley runs upbeat, intense practices year-round. But just as there is something different about the pace of a regular-season game, there is something different about a regular-season practice. That pervades through the team. While much of the building at EverBank Field Monday sat empty for the Labor Day holiday – eerily, noticeably empty – football wasn't empty, and there was nothing dark or empty about the preparations for the opener.

It's here, and now this thing gets real.

"The focus sharpens when you get into the regular season, just because you have an opponent you're preparing for," Wisniewski said. "In camp, we're working on ourselves, which is obviously important. But once they put it on the board today – we've got six games until we play a game …

"That sharpens things up a little bit."

And the reality of the NFL is that as real as Monday felt, this only gets realer as the week goes on. Monday was what Bradley calls an extra work day. There was some preparation for Carolina, but mostly it was on the Jaguars. That's one of the last of those kinds of practices the Jaguars get this season.

On Sunday, we start finding out just how much progress this team made in a critical offseason that leads to an equally important 16-game regular season. There will be urgency and intensity throughout the 'Bank Sunday.

But it was already being felt on Monday in the locker room, a place where the building intensity somehow matched the giddy smiles of dreams coming true.

Not to mention a place where things were quickly getting a lot more real.