It's that time of camp, Bruce Arians said.

It's that time when players get a little bored, and no matter what the warning from the top, it shows up on the field. So Arians was irritated with the Cardinals' practice Monday after a Sunday off.

"It hits you right in the face when you put the sheet up there and there are 18 penalties and 45 mental errors," Arians said, noting that there were "some veteran Pro Bowlers who had five mental errors."

Arians was confident the Cards would respond well later Tuesday, but lamented the fact Monday's was practice time the Cards won't be able to get back.

"I'm disappointed with leadership of the team, because that's their job," Arians said.

-- WR J.J. Nelson (groin) is returning to practice, but Swiss Army knife OL Earl Watford is out after bruising his knee Monday (it actually looked like it could have been worse, although Watford didn't miss a play) and CB Cariel Brooks (quad) is also out for now.

-- Arians thinks WR Smokey Brown (concussion) will be cleared in the next day or two, but the coach ruled Brown out from playing Friday night.

-- There is a chance DBs Tyrann Mathieu and Justin Bethel could come off PUP next week. But Arians said if they are not ready to take part in the two practices against the Chargers, the team will probably hold off.

-- Current frontrunner for quote of camp: Arians said TE Troy Niklas has been playing well, playing like the guy the Cards drafted in the second round in 2014. About this, Niklas was happy. Always good to hear the boss is pleased. "He gets my name confused with dumb mother(expletive) a lot," Niklas said with a smile.