Cardinals coach Bruce Arians (left) saw better concentration from his young players at practice on Wednesday.

The Cardinals have put in place a well-delineated hierarchy since coach Bruce Arians was hired in 2013.

He coaches the players hard and hugs them later, and allows the veterans to police the locker room. Many of the Cardinals' long-tenured stars aren't the jump-down-your-throat type, but prefer to lead by example.

It's worked nicely the past few years, with young players soaking up useful information gleaned from their older teammates. But the Cardinals have struggled to a 1-2 start this season, and Arians said one issue is the lack of preparation from his first- and second-year players.

"We've got young followers that ain't following," Arians said. "We've got good leaders. Carson (Palmer), Larry (Fitzgerald), all those guys. Do what they do. You can't play like them but you can prepare like them. You can take care of your body like them. You can eat like them. You can do all the things that a pro does. Some of them aren't doing that."

Palmer said the issue has been brought up and handled internally. By Wednesday, he had already seen improvement.

When the Cardinals practiced against the scout team, Palmer said the young players did a great job mimicking what's to come on Sunday against the Rams. Arians called it "by far our best Wednesday in a long time. We needed that."

Problems can be exacerbated if left to fester, but the Cardinals believe this one has been nipped in the bud. Arians is known for his unflinching honesty, and he's been happy to share his displeasure with his young players both behind closed doors and publicly.

"I think the message was delivered," Palmer said.

EVAN MATHIS, MICHAEL FLOYD PRACTICE

Right guard Evan Mathis (toe) practiced in a limited capacity on Wednesday after missing Sunday's loss to the Bills.

Earl Watford filled in against Buffalo and had some trouble against defensive tackle Kyle Williams. Arians said much of it had to do with communication when Buffalo ran stunts.

"When you can't hear the guy next to you, it's a whole lot different when you haven't worked with that guy for eight or nine weeks on passing stuff off," Arians said. "And Kyle Williams is a Pro Bowl player."

The return of Mathis would be a lift, as the Cardinals will face another top-tier defensive tackle this week in the Rams' Aaron Donald.

Wide receiver Michael Floyd (concussion) practiced in a yellow non-contact jersey on Wednesday but didn't have any ill effects, Arians said, and he could be out of the concussion protocol by Thursday. Floyd practiced in a limited capacity, as did linebacker Kareem Martin (knee), linebacker Markus Golden (shoulder), safety Tyvon Branch (groin), cornerback Justin Bethel (foot) and safety Tyrann Mathieu (knee).

Defensive tackle Frostee Rucker (knee) and punter Drew Butler (Achilles) sat out, while defensive tackle Robert Nkemdiche (ankle) practiced fully.

Arians said tight end Troy Niklas has no use of his hand and will need surgery. He was placed on injured reserve Tuesday.

For the Rams, defensive end William Hayes (ankle), defensive tackle Dominique Easley (illness) and cornerback Lamarcus Joyner (toe) did not practice. Wideout Tavon Austin (shoulder) was limited.

IRONING OUT THE MOVE TO LOS ANGELES

The Rams' new Los Angeles location works in their favor this week, as coach Jeff Fisher joked his team could bus over for Sunday's game against the Cardinals.

But the transition from St. Louis wasn't easy, as the team didn't have a permanent home for most of the offseason, practicing at the Cowboys' training camp facility in Oxnard, California.

"It's quite a challenge having the last two preseason games being night games on the road and then come back after the fourth and final preseason game and move the entire team to Thousand Oaks," Rams coach Jeff Fisher said. "So, we're getting settled. I've got e-mail up, which is good. TVs are working. I can watch some tape, so we're doing OK."

MARQUI CHRISTIAN CLAIMED BY RAMS

Safety Marqui Christian was waived Tuesday and claimed by the Rams on Wednesday. He was the Cardinals' fifth-round pick this season and was inactive in the first three games.

"He was a good young player," Arians said. "I wish him the best."