ENGLEWOOD, Colo. -- Running back Phillip Lindsay, a product of the University of Colorado and South High School in Denver, wasted little time showing why he could become the next player to pull off the Centennial State trifecta: to play high-school, college and pro football in the state.

But as he walked off the practice field after a successful first day of training camp, Lindsay kept his performance -- and a prominence that belies your typical undrafted rookie -- in proper perspective.

"I got the best advice from Emmanuel Sanders, saying that it's a marathon, not a sprint," Lindsay said. "And that just kind of stuck with me, to understand that it's not just about one day; it's about the long run."

Of course, a sprint downfield and a long run after the catch is exactly what provided one of the most dazzling moments of the day, as quarterback Case Keenum hit Lindsay in space during a seven-on-seven period, using a double move to shake linebacker Brandon Marshall.

"He's going to be a great third-down back," Marshall said. "His routes, his quickness and his speed -- I think he's going to be good."

"I did all right. I have to go back and fix some footwork. Everybody sees the so-called big plays, but it's the little things that matter. It's the protections -- are you making sure that Case doesn't get hurt?" Lindsay said. 

"Everything is all cute and fun when you're making touchdowns. But it's about my steps when I'm running the ball, pressing it so that linebackers can get stuck on their blocks. There's a lot of stuff that I have to work on -- that we have to work on as a running-back group."

OBSERVATIONS

... Devontae Booker was the first running back to receive a carry during the opening team period of Saturday's practice, but each of the Broncos' four other running backs saw first-team repetitions throughout the day.

"Right now, we're looking for guys just to compete," Head Coach Vance Joseph said. "They're all different. It's fun to watch how [Running Backs Coach] Curtis [Modkins] is using them in practice, and how [Offensive Coordinator Bill] Musgrave uses those guys within his schemes."

Each of the running backs had flashes of brilliance throughout the practice. One example came during the first team-period, when Dave Williams took a handoff from Chad Kelly, read the blocking and cut back to the left, giving him a wide-open path to a long gain.

... Rookie wide receiver Courtland Sutton also turned heads, showing off his long stride during a seven-on-seven period, taking a pass from Keenum and bursting upfield for a long gain.

... Denver's front seven started training camp in disruptive fashion by showing that there is more to its pass-rush work than just sacks and pressures. The front seven collectively knocked down four passes at or near the line of scrimmage, intercepted a pass and nearly picked off another.

Defensive end Derek Wolfe opened the day by batting down a Keenum pass at the line of scrimmage. Outside linebacker Jeff Holland and defensive linemen Zach Kerr each swatted away Paxton Lynch passes, while Kyle Peko broke up a Chad Kelly toss at the line of scrimmage.

Outside linebacker Bradley Chubb nearly had an acrobatic interception, but failed in his leaping attempt to corral a Lynch pass. Later in practice, Shaquil Barrett managed to finish the job, picking off a Lynch pass that was deflected at the line of scrimmage.

... Lindsay, Isaiah McKenzie and DaeSean Hamilton all got practice fielding punts under pressure, as Special Teams Coordinator Tom McMahon had them run a drill in which five players converged on them, creating heavy traffic as they fielded their punt.

"It's great, and we have great coaches out there helping us out," Lindsay said. "I came from not doing punts to feeling comfortable back there. Now I've just got to continue to grow on it."

It's a demanding drill in which the players in coverage try to strip the ball from the returner once they've cornered him. Safety Jamal Carter and tight end Matt LaCosse each succeeded once at prying the ball lose.

But the returners had their moments, none brighter than when McKenzie fielded a punt to his right, deked the coverage team and took off to the left, eluding the coverage quintet for what would have been a long return in game conditions.

WEIGHTY ISSUES

... Defensive end DeMarcus Walker is back up to his college weight of 280 pounds, but he looks like he has maintained his quickness. During one repetition in a one-on-one period, he used his first step to burst under the inside shoulder of Connor McGovern, allowing him to get to the spot.

"Hey, listen, I'm going to be quick at 280, 250, 240, 290 -- I'll still be quick," Walker said.

... Shane Ray now sits at a career-high 250 pounds, and used his new-found weight effectively in one-on-one drills, using his upper-body strength and momentum from his first step to push blockers into the backfield.

... Marshall felt fresher than ever working at 225 pounds, his lowest weight as a pro.

"I felt great, man. You know what's funny? I didn't get tired today. It was weird," he said. "Usually, the first day, you go through the bags and you get tired. After the bags, I was kind of like, 'All right, I'm a little lathered up.'

"Then we did the pursuit drill, then we did individual, and [the] team [period] was the real test, and I was like, 'Yo, I feel great!' I felt like I was moving good. I was running good. I'm disappointed in myself on the double-move that I gave up [to Lindsay], but that's more technique than anything -- technique and eyes."

PERSONNEL NOTES

... Right tackle Jared Veldheer took his first practice repetitions since joining the Broncos, opening the team periods at right tackle. He worked four snaps in succession on multiple occasions while splitting first-team repetitions with Billy Turner, who filled in for him during OTAs.

"Obviously, we want to make sure he's healthy and he gets in good football shape," Joseph said. "We know he can play; it's more about his health and keeping him healthy and in good football shape, and making sure we get him to Week 1."

... Ron Leary saw a similar workload at left guard after being kept out of OTAs and minicamp following minor knee surgery in May. Max Garcia took the first-team repetitions that Leary did not receive.

... Connor McGovern and Menelik Watson continued to divide first-team snaps at right guard, as they did during OTAs and minicamp.

DATA POINTS

... Saturday's attendance was 3,417 ... The practice took place under mostly sunny skies after the morning fog receded, with temperatures rising from 65°F to 72°F during the session.