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One year ago this spring, Kris Bryant, Addison Russell and Co. had no idea where the keys to the batting cage were.

OK, so that's an old joke. But it's a good one: Veteran tells rookie, "Go get me the keys to the batting cage." So the wide-eyed rookie dutifully bounds off to find them.

There are no keys to the batting cage.

Get it?

The young Chicago Cubs get it. They get most things. They did when they won 97 games last year and raced all the way to the National League Championship Series. And they certainly do now.

What was supposed to have been a learning-curve year last summer instead became an advanced-degree season. Now battle-tested and roaring with confidence as they break the seal on a season that brings their best chance in decades at a World Series title, their experiences in 2015 will only make them sharper.

During spring training last year, no matter how many snakes he sent slithering by depositing home run balls all across the Arizona desert, Bryant still knew he was headed to Triple-A Iowa to begin the season. For business reasons.

"Everybody knew," Bryant said toward the end of spring camp. "Everybody talked about it.

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"This year, I can just relax and go play. You know where you're going to be. You don't have to worry about anything."

This time last year, Russell was checking out the amenities in Des Moines while preparing for Triple-A, too.

"I didn't even think about trying to make the team," Russell said. "I was just trying to make sure all the Cubs guys saw me and make them think they could use me down the road."

"Down the road" for Russell came late April last year, when the big league club summoned him to Chicago and installed him as the second baseman. Then, on Aug. 7, manager Joe Maddon moved him to shortstop for good and flipped Starlin Castro over to second base.

The Cubs never looked back.

There was no lost year. There was no sacrificed summer during a development phase.

And now, they're so much better for it.

"Oh, they're much more comfortable, they're much more relaxed, they feel like they belong here," Maddon said. "They have a whole different focus, literally.

"You look at their eyes, their eyes can actually focus now as opposed to being glazed over with what's going to happen now, what's going to happen next, how do I do this sort of thing?

"That's pretty obvious to me, the fact that that one year of experience makes all the difference in the world."

It doesn't guarantee a ticker-tape parade this fall.

But it absolutely makes a loose and confident team even more dangerous.

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"Playing all those tight games down the stretch last year, it definitely helped," outfielder Kyle Schwarber said. "And I'm definitely more comfortable. I built a relationship with all of these guys. I still had the same goal in the spring as I did last season: go out and get better and prepare for the season."

Add three key new pieces in outfielder Jason Heyward, super-utilityman Ben Zobrist and starter John Lackey, and the Cubs unquestionably are better on paper.

In the clubhouse, it appears that way, too. Coming off his historical Cy Young season, Jake Arrieta was filthy on opening night in Anaheim, chopping through Albert Pujols and Mike Trout like a weed whacker through brush.

This spring, Arrieta worked hard to mentor some of the Cubs' young pitchers, such as Pierce Johnson. After so much talk about a losing culture in Wrigley Field over the years, this is how that turns around.

"That's the kind of stuff that matters," Maddon said. "And hopefully it's going to make us really good for years to come."

The manager talks about his "lead bulls" paving the way, the battle-tested veterans who know the ropes. But on Chicago's North Side, some of the young players are becoming lead bulls far more quickly than expected.

These Cubs are deeper, and each of the young players who was a "prospect" at this time last year is seasoned beyond what might have been reasonably expected at this point. Club president Theo Epstein last spring fretted that this group was being so hyped that maybe it wouldn't be afforded that quiet growing period that, say, the Kansas City Royals' nucleus had.

So far, it hasn't seemed to matter.

Having Bryant and Schwarber housed in nearby lockers has made it easier for Russell. And having Russell and Bryant in the same clubhouse has made it easier for Schwarber. On and on it goes.

"Whenever you've got young guys in the clubhouse, it makes it easier [to develop]," Russell said. "I played with KB in the Arizona Fall League, and at Triple-A.

"He's a good dude all the way around. He's very humble, and he likes to have fun."

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Said Maddon: "Just roll back the clock to a year ago, all that controversy over KB making the team or not making the team. Addison—we had Starlin at shortstop and other options at second base, although we hadn't even played him at second base, so we had to give him that opportunity to know that he could.

"There were so many things that were different about last year at this time compared to where we're at right now. All positive, obviously, that guys got the experience necessary to go into their second year. And they feel like they belong here.

"I think a lot of guys last year, I don't want to say they were in survival, like Stage 2, but they just didn't absolutely know that they belonged here, even though we knew that they did. They had to find that out for themselves. So once a player finds out for himself that I belong here, I can do this, an entirely different level of confidence arrives."

Even for a veteran like starter Jon Lester, in your second year in a place—job, school, whatever—you become far more comfortable.

"Knowing me better, knowing everybody else around you better, that matters," Maddon said.

"I've been in their shoes, where I had a good first season," said Heyward, who signed in Chicago for $184 million over eight years to chase a World Series title with the Cubs. "You don't have anything to sit on [in that first season], you have no numbers.

"They're trying to become the best version of themselves they can be."

Bryant slammed 26 homers and knocked in 99 runners in 151 games last season. Russell cracked 13 homers with a .307 on-base percentage. Schwarber crunched 16 homers in only 69 games and then ripped five more in nine postseason outings. Outfielder Jorge Soler, also a rookie last season, produced a .324 on-base percentage and 47 RBI in 101 games.

One season in, how real are those numbers? How dependable? Are they high? Low? What?

"I'm more comfortable this year," Soler said, smiling.

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All of these Cubs are.

"Definitely, a year ago, I was in spring training for the learning experience," Schwarber said. "And I got experience. That was my goal last spring.

"My goal this spring was: I want to stay on this team. I don't ever want to go back to the minors. I want to help this team win."

Like Heyward said, they're all working hard to produce the best version of themselves.

"KB is as comfortable here as he was at the University of San Diego," Maddon said, referring to Bryant's baseball home before the Cubs made him the second overall pick of the 2013 draft. "Addy's as comfortable right now as he was in Pensacola [Russell's hometown in Florida]. Schwarber, it's just like he's back at Indiana [the Cubs picked him fourth overall in the 2014 draft out of the University of Indiana].

"I'm certain they're that confident and comfortable as they were when they were coming from that level of strength, regarding their performance and their status in the game at that point. They were the best college players. They were the best high school players. I think they're back there in a professional level in the major leagues right now."

The first two games in Anaheim, it sure looked like it. Their eyes were no longer glazed over. Not even close.

Scott Miller covers Major League Baseball as a national columnist for Bleacher Report.

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