ENGLEWOOD, Colo. — “It’s like the guy that swings the sledge hammer out in construction,” Broncos head coach Vic Fangio said after the team’s fourth consecutive day of practice. “The first few days, he’s got blisters, and his shoulders are sore. By week two or three, though, he’s all good to go. That’s kind of what we’re working through right now.”

The Broncos, in Fangio’s estimation, are taking an important step in the process.

“I think the big thing that happened today is that guys are starting to get calloused,” he said, further explaining the metaphor. “One of the big things about training camp is you have to get calloused to play NFL football. I think some of that started to form today with it being the second day in pads and the fourth day in a row. These guys are getting calloused out there.”

Callous is also a good word for the way Fangio’s defense has treated his offense throughout those four days.

Sunday’s practice featured some unexpected breakouts and some stars making plays. Here’s what we saw during the session that lasted just over two and a half hours.

Flacco’s Frustration

If once is chance, twice is a coincidence and three times is a pattern; four times in a row is reason for concern.

For the fourth consecutive practice, Joe Flacco and the rest of the Broncos quarterbacks were under constant pressure from the defensive front seven, forcing the signal-callers to run for their lives often and rarely get through their reads.

And for the first time, you could tell it frustrated Flacco.

After yet another play that ended in a “sack,” the starting quarterback finally allowed his shoulders to slump a bit as he put his hands on his hips and rocked his head back.

Later, during one of his last reps of a period, the play was blown dead again with multiple players in his face. As he jogged back to the group of quarterbacks, Flacco shook his head.

Asked if he noticed the frustration, Fangio said he did not, but added, “It’s the O-line’s job to build a nice fort for the quarterback to operate in. We’ll see how the fort-building goes after I watch the tape.”

The fort, as it appears, is sagging in some areas.

The good news for the Broncos is that they have a five-practice head start on the rest of the NFL, meaning that Wednesday’s practice would really be their first practice of camp in previous years. Because of that, this offensive line still has plenty of time to gel as they all get used to playing next to someone new.

With that being said, each day that sees immense pressure on the quarterbacks is a reason for concern, and seeing Flacco’s frustration on Sunday was reason enough to pull the benefit-of-the-doubt card away. It’s go-time now.

Noah Fort? Austin Fant?

There’s a metaphor that myself and Zach Bye from 104.3 The Fan love to use in training camp, we call it “the alien.”

The premise is—if a football-knowing alien came down to practice with no pre-conceived notions about the players, they would think ______.

The truth is, if an alien had been at the first four practices of this year’s camp, it would think that undrafted rookie Austin Fort was the tight end that the Broncos drafted in the first round.

So far, it’s Fort who has been the premier tight end with a four-letter last name that begins with an F, and while I wish I could tell you it’s because he has just been phenomenal, that’s not quite the truth.

Fort has been impressive, no doubt, making plays for all four quarterbacks in most practices, as he’s capitalized on each opportunity, but the problem is that Fant has set a low bar.

In two of the first three practices of camp, Fant was forcefully reminded by a teammate that he needs to finish his runs after he makes a catch, and he’s simply struggled to be consistent on the field, despite making some really nice plays, especially in the red zone.

To my eyes, it appears Fant may have come into camp a bit out of shape. He seems to be winded after each rep or drill, and it’s hard to be consistent if you’re tired.

If that’s the case, it’s a bit of good news and bad news. The good news is that, presumably, once he gets into football shape, some of the negatives will subside. The bad news is that a rookie really has no business coming into camp out of shape.

Again, that’s just what it looks like to me. We’ll, of course, keep a close eye on the first-rounder as camp goes on.

Under-the-radar standouts

It’s at this point in camp that you start to say, “Man, that (insert number here) guy just keeps making plays.” So let’s give those guys some credit here in the observations.

You’ve, of course, heard of Austin Fort at this point, but here are some other under-the-radar guys that have stood out so far.

Devontae Jackson, RB, West Georgia

If you can spot little 5-foot-7 No. 48 out there, you’ll see him scooting all over the place.

The undersized back has a lot of burst and has some fancy footwork out in space.

He’s got an uphill battle ahead of him as he attempts to make the roster in somewhat of a crowded running back room, but he’s got the goods.

Mike Purcell, DL, Wyoming

Speaking of former Wyoming Cowboys standing out, defensive lineman Mike Purcell, an undrafted free agent in 2013, is making his prescnece felt early.

Purcell is a local kid out of Highlands Ranch who has really flashed some nice ability to get into the backfield from his position on the interior. It’s been hard not to notice No. 98, and he has familiarity with the coaches.

“He’s just been a tough guy for us,” said defensive coordinator Ed Donatell. “You see every time we put in the scheme, we like having him around. He’s here to build depth and improve himself every time. Over the years, every time a guy goes to a camp, they have a chance to improve a little bit. And those guys have made teams. We really respect the way he works and the way he’s dialing up and giving everything he has again.”

Trinity Benson, WR, East Central

For a speed guy from a small school, Benson isn’t as small as you might think.

Standing a six-feet and 180 pounds, Benson has a bit of length to go with his speed.

“He’s fast. He’s quick. He’s elusive,” said Vic Fangio. “If he can become an NFL receiver, meaning operate efficiently so those skills can surface, maybe we’ve found somebody.”

If you aren’t sure, that’s a compliment from Fangio.

Khalfani Muhammad, RB, Cal

Khalfani isn’t new around here, having spent time on the team last year, but this is his first camp as a Bronco.

It’s abundantly clear that Muhammad, who at 5-foot-7, 174 pounds is the smallest player on the team, has plenty of burst. The second-year back is a menace in space and doesn’t get caught once he’s in open space.

If he can show that he can pick up a blitz, he could have the chops to stick around as a third-down guy.

Other notes

• Drew Lock had his first mistake-filled day, as he threw two interceptions on tipped balls, neither of which were good decisions.
• Kevin Hogan bounced back a bit from his three-pick performance on Saturday.
• DeMarcus Walker got into the backfield a couple times on in practice, including once against the first-team offensive line.
• Things got a bit more chippy out there as the defense was as aggresive as we’ve seen them, having a hard time laying off of hits. Even Joe Flacco was contacted at once point, which got a rise out of the coaches.
• Dre’Mont Jones made some plays on the interior, showing his ability to get in the backfield.
• The “play” of the day came when Brandon McManus “intercepted” an out-of-bounds throw from Drew Lock and ran it all the way back for a touchdown, beating Emmanue Sanders down the sideline. The crowd had fun with that one.