ENGLEWOOD, Colo. -- No matter which cliché you utilize, the sentiment remains the same: an injury or illness to a player is unfortunate, but it creates an opportunity.

But even though the running backs have been through one practice without Montee Ball, they were not yet seeing his absence due to an appendectomy as an opportunity for themselves. Their concern was with Ball, who is arguably the leader of a young corps that includes no one with previous NFL starting experience.

Nevertheless, the runners each bring something different, and with Ball out, they will have more chances.

"You hate to see anything happen to a player whether it's an illness, injury on or off the field," said Head Coach John Fox. "Sometimes when a door shuts, another door opens. It will give us a chance to give the young backs sometime to get in there and hopefully they can grow and progress."

And that's where today's Five Thoughts begins:

1. Ronnie Hillman has seen plenty of work rotating in with the first team, given the platoon nature of running back, so his bump to the top line in Ball's absence was nothing jarring.

"You get out there and get reps with Peyton (Manning) and you actually get the speed of the game," he said. "It's better when you actually get reps with the ones, and now you've got to take advantage of it."

His play during Monday's practice was no surprise, particularly on a run where he burst up the middle through a hole to the right of the center and had a full head of steam before contact nearly 10 yards upfield.

"Ronnie is obviously our change-of-pace guy, and our fastest guy in that room, as you look at him on film," said rookie Kapri Bibbs.

He also has experience and, the Broncos hope, increased maturity. In June, Hillman noted that he "relaxed" last year, and said that in 2014, he wanted to be "accountable" -- to make fewer mistakes, and be more dependable. He has done that so far.

2. C.J. Anderson doesn't have the experience with the first unit that Hillman has, but he had just enough last year for a base upon which he could build. He's expanded that this year, with particular improvement in pass protection. That was on display in Saturday's Summer Scrimmage when he picked up a blitzing Nate Irving to keep Brock Osweiler upright. Two days later, he kept T.J. Ward at bay.

These plays are evidence of his description of his improvement in pass protection: "Just tremendous."

"Just staying in my playbook and continuing to look over, continuing to see. It's just been helping out a lot and it pays off," Anderson said. "Even that blitz pickup I picked up today on T.J., it's helped out a lot, being (in my a second year in the offense and (having) actually played in some games last year and (getting) to see how we run when we run when we run with (Manning)."

That shows Anderson's composure under fire. Even in the middle of chaos, Anderson appears calm, an eye of stability in a swirling storm of 250-pound humans.

"C.J. brings a lot to the table: his awareness, his I.Q. for the game," Bibbs said.

That comes with knowing his job, knowing the playbook and knowing what Manning needs from the running back.

"I've always said, 'Keep your head down; keep grinding.' If I keep doing the things I'm doing, everything will pay off for itself," Anderson said.

"It's not like last year, if Montee or Knowshon (Moreno) would have gone down, and I'm a rookie learning the offense. I know the offense, and I'm real comfortable, and I feel like 18's comfortable, and I'm comfortable, and I can just keep pushing."

3. Hillman and Anderson were certain to get plenty of repetitions. But the opportunity for advancement could be greatest for Bibbs, Juwan Thompson, Jerodis Williams and Brennan Clay.

Thompson is atop the depth chart among that group, and has two advantages: experience in a complex offensive system and versatility. At Duke, he caught 56 career passes, returned kickoffs and even played linebacker.

Thompson does a lot of things well. But Bibbs, Clay and Williams were prolific in college. Their work Thursday could set up one of the most intriguing battles of camp: for the No. 4 spot that might carry a 53-man roster spot with it (it did last year, which benefitted Anderson).

4. Demaryius Thomas' return in the past week following the death of his grandmother has meant that more of Cody Latimer's repetitions have come with the second team than the first. That has its advantages for Latimer, who continues to work with Manning after practice, but now is developing his timing with Brock Osweiler. That could prove vital for the future, whenever Osweiler succeeds Manning under center.

They throw different types of passes. Manning's are predicated on precision and placement, while Osweiler throws some high-speed bullets when the need arises.

"They both make some great throws. They're both great quarterbacks," Latimer said.

The differences come before the snap.

"Peyton checks to many different things. Brock checks to a couple different things, but he likes to tell us, make sure for sure we know what we have. Peyton's like, 'I'm going to tell you this, you're going to run a go (route), so you've got to know it.'

"So it's just a faster pace with Peyton, but they're both great quarterbacks and they're both putting the ball where it needs to be."

5. In his third training camp, Omar Bolden has been more consistent and has made quicker, better decisions in coverage than during his first two NFL seasons. He does a better job at keeping receivers in front of him, and has improved his tackling, limiting yardage after the catch.

Some of that improvement is due to his experience, but his work at safety last year was particularly valuable. He was moved there at the end of the preseason and stayed there the rest of the season, playing extensively against the Chargers in December.

But it wasn't a natural fit for him, and he moved back to cornerback this year -- with a better awareness of how to play defense within a team, rather than just one-on-one.

"It definitely made me smarter and more aware of where my help is at," Bolden said. "But I'm just way more comfortable on the outside.

"I'm glad to be back at corner. I feel comfortable out there."