The Cardinals have been diligent about following protocols throughout training camp and remain one of the few teams yet to place a player on the COVID-19 reserve list.

However, another issue arose on Sunday, when 10 teams – which didn't include the Cardinals – received positive coronavirus results that may have been falsely categorized.

The Bears announced they had nine test results that were ultimately deemed to be false positives. Some teams held players out of practice as a precaution, and guard Justin Pugh is hoping a similar situation doesn't arise on game day during the season.

"It's definitely a concern," Pugh said. "I'm glad we're starting to figure the kinks out now, while we're in training camp. I think that's part of the reason why we're doing things the way we are – to figure out what works and what doesn't work. We're battling an unknown virus, an unknown scenario, an unknown landscape we're in right now. So we have to be able to roll with the punches, and obviously we had some hiccups this past weekend. We learned from it, and hopefully it doesn't happen again, because you'd hate to see a guy miss a game with something like that."

On Sunday morning, the NFL said it was looking into the irregularities.

"Saturday's daily COVID testing returned several positives tests from each of the clubs serviced by the same laboratory in New Jersey," it said in a statement. "We are working with our testing partner, BioReference, to investigate these results, while the clubs work to confirm or rule out the positive tests."

Overall, the coronavirus situation in the NFL has been handled impressively, as there are only three players leaguewide on the reserve list.

Running back Chase Edmonds admitted he was initially skeptical about getting through the season -- especially after seeing early outbreaks in Major League Baseball -- but changed his outlook when the players reported for camp.

"Seeing the methods we're using, I have complete confidence that we can get this thing done," Edmonds said.

Defensive coordinator Vance Joseph has been encouraged by the players' adherence to the protocols, but said it is important to prepare for unexpected absences.

"So far our players have been on it," Joseph said. "They've been diligent in the protocols. No one is complaining about it. Man, I tell you, I've been so proud of our guys on defense for doing the right things. But I think you have to have a plan. With this virus, there are no guarantees. You have to have a plan if you lose a guy or two, or even a coach or two."

KINGSBURY'S PLAY DESIGNS IMPRESS JOSEPH

Joseph was an NFL head coach for two years and has been in the coaching ranks since 1999, so he's seen plenty of football.

Even so, there are things coach Kliff Kingsbury does during practices that still catch him off-guard.

"It happens all the time," Joseph said. "He ran two plays today in an inside (run) drill where he pulled both tight ends and pulled the guard, and it was a gaping hole. ... When you combine Kliff's run game with (offensive line coach Sean Kugler's) run game from Pittsburgh, it's tough. (Kingsbury) has run schemes and concepts that I haven't had answers for in practice. You have to go back and figure it out. It makes both sides better."

HOPKINS DOESN'T WORK INDIVIDUAL DRILLS

Wide receiver DeAndre Hopkins warmed up at the outset of practice but didn't participate in individual drills during the portion open to the media. Others not participating in the open portion included outside linebacker Chandler Jones, defensive tackle Corey Peters, tight end Maxx Williams and tackle Kelvin Beachum.

Williams hasn't practiced all week with an unspecified injury. Tight end Dylan Cantrell was practicing in the open portion for the first time in camp.