ENGLEWOOD, Colo. -- Each day of OTAs, minicamp or training camp provides a different kind of test. For the quarterbacks, Tuesday's first minicamp session provided an examination of their poise.

Denver's front seven -- with the occasional aid of its safeties -- cranked up the heat on all three quarterbacks throughout the practice.

At times, the offense was able to adapt. One example came midway through practice, when Case Keenum faced down a blitz up the middle and quickly spotted rookie running back Phillip Lindsay tucked in behind a defender near the line of scrimmage. Keenum hit Lindsay, and the speedy rookie took off for a long gain, showing the offense's ability to exploit a heavy rush.

Two snaps later, Keenum delivered again, dodging a rush from Todd Davis to find an open Jeff Heuerman near the left sideline.

But on the two plays that followed, the defense responded with vigor. First, DeMarcus Walker swatted down a Keenum pass in the backfield. On the next snap, Bradley Chubb leapt to knock down a pass despite being engaged with two blockers.

That sort of give-and-take in pressure scenarios was a positive for the Broncos. It expanded the possibilities of young pass rushers like Chubb and Walker.

It also demonstrated Keenum's ability to make quick decisions and exploit areas vacated by pass rushers. Keenum demonstrated that in his work with the Vikings last season, posting a 78.5 passer rating when pressured, according to Pro Football Focus.

That placed him seventh in the league among quarterbacks who took at least 25 percent of their team's snaps. It was also 13.9 rating points above the league average and 36.4 rating points over what the Broncos posted last year.

"The defense mixed it up a little bit and brought some good pressures, so we have a lot of good tape to watch from today," Keenum said.

"We did some good things, but there are a few balls I want back. We're growing and we're learning. It's spring. From where we are today from where we were a month ago, I think we've made some big steps. There's a lot to grow on, too."

For the defense, there is also plenty of room to grow from last year, when the Broncos ranked 17th in the league in sack rate, bringing down opposing quarterbacks once every 15.9 pass plays. That represented a steep decline from 2016 (5th, one every 14.1 pass plays) and was a far cry from 2015 (1st, one every 12.0 pass plays).

Bringing the Broncos back to their 2015 pass-rush prowess is one reason why they drafted Chubb. It also explains why pass rushing has been a point of emphasis this spring.

"We're definitely working on it," inside linebacker Brandon Marshall said. "I'm not sure where we were in sacks last year (22nd with 33 sacks), but we have these [practice] periods where we have first, second [or] third-down pressures.

"We want to put pressure on the quarterback. I think that's what made us so successful in 2015 when we won the Super Bowl. We put pressure on them. We played Tom Brady in the AFC Championship Game and we hit him [17] times. So I think that's the key. Last year we kind of lacked on it, so they want to work on it."

So far, so good. During the four practices open to media observation in the past four weeks, pressure from the front seven -- supplemented occasionally by safeties -- has been a constant, offering a sign that the defense should be able to have a bounce-back season.

The pressure also opens up horizons for the defensive backs. Chris Harris Jr. picked off a Keenum pass intended for Isaiah McKenzie near the left sideline, and outside linebacker Marcus Rush nearly picked off a Paxton Lynch pass intended for Courtland Sutton that was released as rookie Josey Jewell brought pressure from the inside.

"It's going to help us out a lot, man," safety Darian Stewart said. "Those guys up front have been doing great things. [Defensive Line Coach] Bill [Kollar] is working them. Even when we've got seven-on-seven, he's making sure that they get their work in. I think they're going to be a lot better this year, and it's going to help us get a lot of [interceptions]."

Days like Tuesday offer the Broncos hope that their pass rush can return to its overpowering form.

OBSERVATIONS FROM THE PRACTICE:

All three offensive units found success in a move-the-ball period that saw the offense take over at its 40-yard line.

Keenum led the No. 1 offense to a pair of first downs before its turn was wrapped up. He completed three of four passes on the drive, finding Andy Janovich, Emmanuel Sanders and Royce Freeman.

Lynch marched the No. 2 offense 60 yards to a touchdown against the second-team defense. He completed all six of his passes on the drive, with half of them going to Courtland Sutton, including a 9-yard strike for a touchdown on a quick slant route.

Kelly converted two third downs on six plays before the horn blew on his turn. On the first connection, a third-and-6, he rolled left after the line picked up a blitz from Joe Jones and found River Cracraft for a 6-yard gain.

Three plays later, with the offense in third-and-2 after a pair of Freeman runs, Kelly hit John Diarse on a slant route to move the chains. The horn blew to end the period after that.

... Kelly had his ups and downs Tuesday, but had one of the best plays of the day, hitting tight end Matt LaCosse in stride for a long reception down the seam that would have likely been a touchdown in game conditions.

... It was a strong day for the Broncos' three rookie running backs, all of whom had explosive plays throughout the practice.

Seventh-round pick Dave Williams had perhaps the strongest run of the day, sweeping left and waiting for the hole to develop before bursting through it and galloping down the left sideline for a long gain. Williams and Freeman's vision, patience and decisive cuts have led to a slew of lengthy carries over the last few weeks.

Lindsay was active in the passing game, serving as a crucial outlet for all three quarterbacks under pressure. He frequently turned his receptions into lengthy gallops.

"He'll be a good scatback," inside linebacker Marshall said. "I think he'll be a great third-down back. He's quick. I think he can create some matchup problems."

"The running backs, all of them are doing a great job," Stewart added. "They're going to help us win a lot of games."

... Second-team defensive backs Dymonte Thomas and C.J. Smith each broke up passes from Lynch during a practice period. Thomas dove to swat away a pass from tight end Jake Butt, while Moore lunged to deflect a pass before Cracraft could nab it.

Thomas, who played in three games late last season, has caught Stewart's eye.

"He's been doing some great stuff [and] he's going to be doing some great stuff for us," Stewart said.

... Diarse was active once again. During one period, he caught consecutive passes from Kelly, first making a tip-toe grab near the right sideline, then hauling in a pass on a slant route despite blanket coverage from first-year safety Jordan Moore.

... On May 24, Marshall said at a press conference that he wanted to lose weight so he could do a better job covering tight ends, noting his goal was to be at 227 pounds.

Tuesday morning, Marshall said he weighed in at two pounds below his goal, checking in at a lean 225 pounds. It has shown in his play, as he looks faster in coverage than in previous years.

"At OTAs, I lost 11 pounds," he said. "I want to be able to more efficiently. I want to feel better on the field. I want to have less body fat. I think that's important.

"I could be 240 [pounds], but if I've got a lot of body fat, it's going to slow me down. I want to get down, and then in these next five weeks when I'm off, I can focus on my strength training and build muscle. I want to just lose the fat and be stronger, leaner and more effective."