Seven observations from Vikings camp: Referees bring the noise at practice with Broncos

The return of joint practices at TCO Performance Center on Wednesday between the Vikings and Broncos also came with the return of practice referees.

And it was the refs who caused the most noise during uneven practices for quarterbacks on both offenses. Right out of the gate, during 1-on-1 receiver and defensive back drills, Vikings corner Patrick Peterson was flagged for illegal contact on Broncos receiver Kendall Hinton. Then Vikings corner Bashaud Breeland strongly questioned a similar defensive flag for his coverage.

"They got a little flag-happy at the beginning," linebacker Eric Kendricks said after practice. "But it makes us focus in a little bit more, makes us dialed in."

Broncos receiver Seth Williams later doubled up on penalties when he was flagged for pushing off Vikings corner Dylan Mabin during a red-zone touchdown catch. Williams was then penalized for taunting Mabin on his way back to the huddle.

"That's $14,000 right there," Vikings corner Mackensie Alexander told his teammates on the sideline, referring to the NFL's fine system.

Here are more observations from the first Vikings-Broncos joint practice:

None of the quarterbacks was particularly on point. Vikings quarterback Kirk Cousins sailed a pass over tight end Irv Smith Jr.'s head early in passing drills. He was most efficient firing slant and underneath passes to receiver Adam Thielen, who was targeted often while Justin Jefferson (shoulder) watched from the sideline. Cousins drew Broncos edge rusher Von Miller offside with a hard count. But on the following play, Broncos defensive end Shelby Harris batted down a Cousins pass at the line. Cousins ended practice with a drive that included a missed screen pass to running back Alexander Mattison, and a misfire too far in front of running back Ameer Abdullah.

Broncos quarterback Teddy Bridgewater was the second fiddle to Drew Lock, who will start Saturday's preseason opener vs. Minnesota. Neither of Denver's QBs particularly impressed on Wednesday afternoon. While Bridgewater completed every pass of his first 11-on-11 session, he was spotty in a 7-on-7 passing drill. He opened by threading a downfield pass to tight end Eric Saubert on a post route, but followed by sailing a deep pass over receiver Tyrie Cleveland and a pass behind receiver KJ Hamler in the flat. Bridgewater's touch passes were the most efficient, as he found Hamler and receiver DeVontres Dukes with lofted passes for touchdowns to end a red-zone passing drill. Vikings nose tackle Michael Pierce deflected a Bridgewater pass at the line. Lock's final team session ended with an interception by Vikings safety Xavier Woods.

There was no bubble wrap on running back Dalvin Cook, who looked phenomenal bouncing runs to the outside, where he evaded Broncos defenders left and right. Cook was plenty involved with the first-team offense on Wednesday, but it remains to be seen how much coach Mike Zimmer will use him in the preseason. Defensive end Danielle Hunter appeared to get a veteran's day off, as he participated in warmups but did not wear pads. Left tackle Christian Darrisaw was nowhere to be found, just hours after Zimmer said he would not be playing in Saturday's preseason opener. Darrisaw is still recovering from a lingering groin injury that was surgically repaired in January, and had been participating in offensive line drills before Wednesday.

Receiver Blake Proehl was carted off the field after going down in passing drills. Vikings athletic trainers looked at Proehl's right leg before helping him onto the cart. The undrafted rookie's knee appeared to buckle while cutting on a route. Alexander, the slot corner, also went inside with trainers toward the end of practice.

Kicker Greg Joseph is going to get every attempt Saturday vs. Denver, according to Zimmer, and he got every kick on Wednesday as well. Joseph made all six field goal attempts against the Broncos, including five straight during a field goal period. His current competition, undrafted rookie Riley Patterson, has attempted only a handful of field goals since returning from the foot injury that had him on the physically unable to perform list to start camp.

Defensive end Jalyn Holmes was more involved with Hunter sidelined on Wednesday. The 2018 fourth-round pick got the first crack as the fifth lineman in a defensive subpackage the Vikings have used quite a bit in camp. The look features second-year end D.J. Wonnum in a stand-up role, either off the edge or aligned as a stack linebacker. Defensive end Stephen Weatherly lined up off the other edge. The Vikings have a logjam at defensive end, where rookies Patrick Jones II and Janarius Robinson are competing for those depth spots previously occupied by Holmes and Hercules Mata'afa, among others.