An NFL locker room often is a collection of close-knit position groups, drawn together by all the time each group spends in the meeting room and their shared skills, all tied a little more loosely together in the context of the team at large.

Given the ever-changing nature of NFL rosters, the biggest personalities often belong to long-tenured veterans who have built deep friendships together over time.

Alden Darby transcends position, playing time or longevity.

Darby, a little-known safety who joined the practice squad in September, has become one of the team’s most popular players — a smiling, laughing bundle of boundless energy who might be doing cartwheels on the field between drills, be right in the middle of a heated debate about the NBA or be needling his teammates at the pingpong table that now occupies one side of the locker room.

“ ’Cause he’s the loudest guy,” cornerbacks coach Aaron Glenn said. “If you’re the loudest guy, you’re the guy everybody wants to talk to. But yeah, he’s a character, for one. Usually, those guys are always loved by the group. You can joke with him, and he can joke with everybody. He’s not a sensitive guy, so you can bring him anywhere you want to, (and) he’s going to come back at you.”

Darby’s oversized personality is something of a rarity for a player who hasn’t taken an NFL snap.

But that’s how he has always been. Darby, who went undrafted out of Arizona State, spent 2014 training camp with San Diego and 2015 camp with Pittsburgh before latching on with New Orleans last season, only has one setting.

Full-bore, consistent enthusiasm always ends up earning him a place in the locker room.

“When you first get here, a guy like me who goes hard and is energetic, when you first get in the locker room, guys think you’re trying too hard, that it’s kind of fake,” Darby said. “But once you’ve been here a while, guys know who I am, they’re like, ‘That’s Darby.’ ”

What Darby’s teammates always come to appreciate is that his personality springs from a place of genuine joy. A lot of players in Darby’s position, undrafted and cut twice already, would get a little worn down by the disappointment and uncertainty of chasing the NFL dream without the prize of playing in a game.

Darby still sees the NFL world with wide-eyed wonder.

“No matter what I’m doing, being able to walk in this locker room every day ... I’ve got friends, family members, friends of friends that would kill to be in my position, no matter what it is,” Darby said. “No practice squad last year (for them); no being brought back for another opportunity here. They would just love to be here. My way of showing the man above that I appreciate him is coming out here and being happy with a smile on my face, and never being sad. You’ll never see me sad.”

Darby’s enthusiasm adds another jolt of electricity to a Saints secondary that already is the liveliest corner of the locker room.

Every team needs players with that kind of enthusiasm. Finding somebody who doesn’t need to manufacture it is no easy task.

“It’s just who I am; it’s not something you can fake,” Darby said. “It’s not something where you can go around and say, ‘I’m going to get these guys energetic. I’m going to get these guys hyped.’ I’m going to be hyped, I’m going to be energetic, I’m going to be happy, I’m going to spread energy with my teammates and spread the love around.”

Darby once again faces a difficult battle to make the 53-man roster. New Orleans already has Kenny Vaccaro and Jairus Byrd entrenched as starters; second-round pick Vonn Bell will have a role; CFL import Erik Harris has been much better than advertised; and the re-signing of Roman Harper suddenly makes safety one of the deepest positions on the defense.

No matter. Darby has attacked the offseason, partnering with Vaccaro to learn how to better prepare himself to battle for a roster spot.

“He’s a real hard worker already, and I kind of pushed the envelope,” Vaccaro said. “But that’s just the way he is; he’s going to go full-speed in every drill. He’s going to be that guy you want on your team. I’m hoping he’s here.”

Vaccaro is far from the only Saint who’d love to have Darby lighting up the locker room this season.