ENGLEWOOD, Colo. — Life as a rookie in the NFL is hard, to say the least.

Along with their lives being flipped upside-down and going from competing against other collegiate athletes to now full-grown men, there is another aspect that makes it a difficult transition: Many veterans don’t bother to even learn their name.

“Right now, I call them by their number, like 55,” Domata Peko — a.k.a one of the kindest humans on the planet — said on Wednesday when talking about rookies. “I just try to call them by their number. But that’s just a rookie thing, you’ve got to earn the respect of the veterans.”

In Peko’s way — which is adopted and used by many veterans across the league — rookies won’t be called anything other than their number until they make the final 53-man squad at the end of the summer.

However, although that’s still nearly three months away, during the second day of the Denver Broncos’ OTAs, four younger players stood out to the vets they are trying to gain the respect of. The first, and most obvious for a variety of reasons, was John Elway’s prized acquisition of the offseason.

“He’s a big kid, and he can run. He can get that speed and power going,” defensive end Derek Wolfe said about first-round pick Bradley Chubb. “He’s going to be a good addition.”

After drawing praise from the most intimidating player on the Broncos, Chubb cashed in again, this time from the opposite end of the spectrum.

“I really like Chubb. Just seeing him on the first day, he reminds me of Von [Miller] a lot,” Peko said, making the lofty, yet understandable, comparison to the Super Bowl MVP. “He’s quick, he’s strong, he can get to the passer, he’s disruptive, he’s willing to learn. He’s always talking to Von asking him like, ‘Hey what can I do?’ And stuff like that. It’s good to see out of a rookie.”

It’s unsurprising the 6-foot-4, 270-pound edge rusher is already drawing rave reviews from his teammates — he was, in fact, the fifth-overall pick in the draft and the second-highest drafted player on the entire team.

However, immediately after the 13-year veteran defensive tackle praised Chubb, he went out of his way to point out two other rookies who have caught his eye early in OTAs.

“We have that big receiver from SMU also,” he said, speaking about second-round pick Courtland Sutton. “He had a good catch yesterday. He ‘Mossed’ somebody I think.”

During Tuesday’s first OTA practice of the year, the 6-foot-4 talented receiver did, in fact, reach into the Randy Moss book of tricks and deliver a textbook ‘Mossing’ to cornerback Brendan Langley.

With a 50-50 ball in the air down the left sideline, Sutton went up and over smothering coverage to secure the ball over Langley’s head. The 22-year-old then had the composure to secure the ball despite a body being in the way and get both feet down.

Peko wasn’t done talking about rookies that have impressed him, though, even if he didn’t get their name right. Unprompted, Peko praised “Jo-el, the guy from Iowa,” as he called him, referring to fourth-round linebacker Josey Jewell, stating, “he’s been looking really good.”

Along with the typical banter about Case Keenum and the leadership he brings to the team, there was one non-rookie that drew unsuspected praise: Former second-round pick DeMarcus Walker.

“First thing, he’s put on some weight. His effort level is way above where it was,” Wolfe said in a powerful tone talking about the now-second-year defensive end. “[Defensive line coach] Bill [Kollar’s] pushing him trying to make him better. He’s trying to compete with everybody; he’s not complacent. He’s trying to get better every day. I’m proud of him.”

After a rookie season in which Walker only compiled a single sack as he bounced around from being a defensive end to an outside linebacker, this offseason the Broncos officially made him a pure defensive end.

Although talk this time of year typically is positive about every draft class, the veterans have already noticed a difference about this class that they hope truly makes a difference in the type of impact they will have this year.

“There’s no complaining,” Wolfe said firmly after admitting this year’s draft class is “absolutely” a mature group. “That’s the one thing that you notice from an immature draft class is they complain a lot and whine and cry a lot. There’s none of that coming from this group.”

Remember, this praise is coming from a man that’s not afraid to voice his opinion “no matter what” and is “never just going to feed you guys bulls*** to feed it to you,” as he reminded the media on Wednesday.

“Most of these rookies are really hungry to learn, are really hungry to win. I’m excited to have them part of the team,” Peko added on with his usual warm smile stretching across his face. “I was telling somebody ‘Man these guys are going to make a difference for us and are only going to help our team.’ I love our new guys and are excited to see what they can bring to the table and help us win games.”