ENGLEWOOD, Colo. — If you're a rookie trying to impress Derek Wolfe, what you don't say may matter even more than what you do.

Two days into OTAs, the 2018 rookie class seems to have learned that lesson well.

The group — which John Elway and Vance Joseph have repeatedly praised as mature — is already proving its mental fortitude.

"There's no complaining," Wolfe said Wednesday. "That's the one thing that you notice from an immature draft class, is that they complain a lot and whine and cry a lot.

"There's none of that coming from this group."

The early flashes of the class' maturity and on-field ability left Domata Peko Sr. with a positive impression as he headed off the field following the second practice of OTAs.

"I'm excited just from seeing them in the two days," Peko said. "I was telling somebody yesterday, 'Man, these guys are going to make a difference for us.' They're only going to help our team. I love our new guys and I'm excited to see what they can bring to the table and help us win games."

Outside linebacker Bradley Chubb, whom the Broncos selected with the fifth-overall pick, is just one of the players who falls in that category.

Peko said he really likes the NC State product and that the 275-pound edge rusher already reminds him of Von Miller.

"He's quick, he's strong and he can get to the passer," Peko said. "He's disruptive, you know? And he's willing to learn. He's always talking to Von and asking, 'Hey, what can I do?' That's good to see out of a rookie."

Chubb's "speed to power" transition also impressed Wolfe, who predicted the rookie would be an important addition to the defense.

Linebacker Josey Jewell is another player who made an early impression on Peko, and wide receiver Courtland Sutton caught Peko's attention with a highlight-reel catch on Monday.

"He ‘Mossed’ somebody," Peko said.

Until the three players make the 53-man roster at the end of the preseason, though, Peko will continue to refer to the rookies by their numbers.

"Make that 53-man roster, then I'll learn your first name and second name," Peko joked. "Until then, I just try to call them by their number. That's just a rookie thing. You've got to earn the respect of the veterans.

"But most of these rookies, like Wolfe said, are really hungry to learn, really hungry to win. So I'm excited to have them as part of the team."