Cardinals coach Bruce Arians greets Chargers coach Mike McCoy after Arians' return to practice Wednesday.

SAN DIEGO – B.A. was back.

After a scary night in which the Cardinals coach had to be hospitalized for a bout of diverticulitis – an infection in his colon – Bruce Arians returned to the team hotel Wednesday morning and returned to the practice field in the afternoon when the Cards had a second workout with the San Diego Chargers.

Arians briefly met with the media beforehand and insisted it was "nothing serious."

"I'll go to practice today and see how it goes," Arians said. "I'm too old to not listen to doctors anymore."

Arians made his appearance, although he as planned left during the workout to return to the hotel. His availability for

Friday's preseason game against the Chargers has not yet been addressed.

"It was meaningful," defensive tackle Calais Campbell said. "He's such a presence. He spoke before practice started. It was just good to see him, a smile on his face."

Arians said when he first started suffering stomach pains before Tuesday's practice at the Qualcomm Stadium, he thought it was a kidney stone. The team's medical staff quickly figured out what the problem was, he said.

Arians had recently undergone a colonoscopy and was told it was possible he could develop diverticulitis. He will have to change his diet some – "No big deal," he said – but he had already been adhering to a strict diet anyway.

Before this week of morning outside practices in Arizona and then different practice times against another team, Arians had said it was good the Cardinals learned how to face adversity. Having the coach go to the hospital certainly qualified.

"I did it on purpose," Arians deadpanned.

"I'm mad I missed the practice (Tuesday) because it was a good one," Arians added.

Cornerback Patrick Peterson said it wasn't that hard for the players to work Tuesday even after Arians was

gone because the message had been delivered that Arians would be OK.

Peterson saw Arians in the lunch room before practice and said he saw "the same ol' B.A."

"We know coach is a trooper, he's strong," Peterson said. "We know he wouldn't want us showing any pity on the practice field."

He wouldn't want the Cardinals showing any regression either.

"(The past 24 hours) have been something, having to deal with that, something that just fell on us," linebacker Kevin Minter said. "It wouldn't be right if we didn't come out and continue to do what we do, because you don't want coach to come back and we took some steps back."

Arians started practice Wednesday walking over to the second field where the Cardinals were working. He shared a hug with Tyrann Mathieu and greeted a few other players before having a conversation with Chargers coach Mike McCoy.

He left at some point during the practice, but as the Cardinals proved Tuesday night, it was not difficult to operate without the head coach because practices are scripted.

 "Obviously if it were a game it'd be different because he's calling plays," quarterback Carson Palmer said.

Arians had insisted in appearing at practice Wednesday. That was not going to surprise any of his players, who already had predicted a result along those lines.

"He's as tough as anyone in that locker room," Palmer said. "I'm sure he was 'I'm good, I'm good, I'm fine,' trying to jump out of the bed and get to the field. Just to know he's back is great news."