Mike Stoops, shown here in the spring, was more vocal at practice Friday. Photo by Michael Chow/The Arizona Republic

Arizona held its second day of fall camp, starting again at 6:15 a.m. at the Rincon Vista Complex. The Wildcats got the benefit of cloud cover for 45 minutes before it turned into a sunny, still, steamy morning.

Speaking of steamed …

Coach Mike Stoops, after seeing redshirt freshman safety Josh Robbins let receiver Dan Buckner slip down the sideline for a big gain in a 7-on-7 drill, came racing — and raging — across the field. It was a pretty healthy chewing out by Stoops, who had a relatively calm observational first day at practice.

Early drills without pads are tough on the defensive backs, not having the benefit of a real pass rush. But Stoops said he was pleased with his secondary against a talented group of quarterbacks and receivers. That’s strength against strength in Arizona’s practice.

“I really like what our secondary is doing right now. I think it is making our receivers and quarterbacks have to execute. Protection needs to improve on the offensive line. But I like our kids and I like the way they practice.”

He said it

“I have been really impressed with our defensive ends. I think they’re doing a great job. C.J. Parish and Mohammed Usman bring a lot of energy. They’re guys who haven’t played much but have been waiting for opportunities for five years to play. They want to take advantage of it, and that’s really exciting for me to see.” — Stoops

Newsworthy

Freshman signee linebacker Domonique Petties hasn’t reported to camp, and it does not appear he will be eligible. Petties, from Duncan, Okla., had transcript and eligibility problems in high school, and Arizona has been unable to resolve those problems with the NCAA.

“We’ve exhausted a lot of time trying to get this process to work in our advantage, but it doesn’t always work,” Stoops said.

Lineup watch

Petties was one of three high school linebackers to sign with Arizona in February, the others being Rob Hankins and Hank Hobson. Hankins arrived with the most fanfare, but Hobson might be the one to get a chance to play right away.

“Hank Hobson is a guy who I think can play early for us,” Stoops said. “I don’t know if we’ll play both of them.”

Hobson is listed as the backup to David Lopez at strongside linebacker, a position that often gets replaced in the lineup by the nickel back. Lopez, a junior college transfer, can also be used as a backup to Derek Earls at middle linebacker, thereby pushing Hankins to third string.

He said it, part II

“I like coaching tough guys. I like coaching guys that are conscientious. I like coaching guys who are dependable. I like coaching guys I can trust. Those are the qualities I look for in recruiting and those are the guys I enjoy to coach.” — Offensive line coach Robert Anae.

Noteworthy

Arizona’s practice ended with the offense scoring a touchdown in a two-minute drill. The score came on a 30-yard pass as Nick Foles passed to a wide-open Dan Buckner, who had slipped past safety Marquis Flowers. … JC transfer linebacker David Lopez is wearing No. 18, a bit strange for a linebacker (but Xavier Kelley did wear No. 15 for the Cats). Anyway, what does Stoops like about Lopez so far? “Big guy. Very physical. Likes to play downhill.” … Arizona athletic director Greg Byrne stopped by practice for a look at the Wildcats. … Freshman defensive back Cortez Johnson did not dress out for the second consecutive day, but Stoops said he anticipates Johnson’s status to soon be resolved satisfactorily.

Paul Vassallo will be trying for his second season with 100-plus tackles. Photo by David Kadlubowski/The Arizona Republic

Here is the eighth part of our Arizona Wildcats football preview in collaboration with our Gannett partner, The Arizona Republic.

We write the words, and they have taken the cool photographs and put it all together in a slick presentation at azcentral.com.

Check back here and at azcentral.com every Friday as we roll out more of our preview every week, all the way into August.

This week: The linebackers.

INTRO

It has been an offseason of attrition at linebacker, but Arizona’s two leading linebackers — seniors Paul Vassallo and Derek Earls — return.

Backups R.J. Young and Trevor Erno left the program, starting linebacker Jake Fischer suffered a torn ACL in the spring game, and there was an academic casualty. That left Vassallo and Earls as the only scholarship linebackers before freshman reinforcements arrive for camp in early August.

“We can’t stop because some people quit or someone went down,” Earls said.

If Vassallo and Earls stay healthy, then this will be a position of strength for the Wildcats, who use just two linebackers the majority of the time, relying more on their nickel package.

But the newcomers, led by freshman Rob Hankins, will have to play some right away — and be ready to play a lot.

Paul Vassallo

Vassallo has been one of coach Mike Stoops’ best junior college finds, leading the Wildcats in tackles last season with 102 and earning honorable mention all-conference honors.

More than that, he became a leader on the defense in his first season in the program.

“Paul is a very outspoken man,” linebacker Derek Earls said last year. “Paul gets offensive really easily. It’s pretty funny. He is usually the first one to go off.”

Said Vassallo: “I like it when things are done the right way, so when things aren’t going as smooth, it kind of frustrates me at times. So then I will say something.”

Vassallo was the first Arizona player to reach triple digits in tackles since Spencer Larsen in 2007.

Derek Earls signs autographs after the spring game. Photo by David Kadlubowski/The Arizona Republic

Derek Earls

Earls, following a successful debut season as a junior college transfer in 2010, brings toughness and savvy to the middle linebacker position. He made 44 tackles, including 6.5 for loss, last season.

He and fellow starting linebacker Paul Vassallo became roommates and fast friends after each arrived at UA for the 2010 spring semester. That chemistry should only be better on the field in their second seasons.

“In the first year, we were a little bit hesitant, trying to make sure we were in the right spot. We really weren’t going 100 percent sometimes because we didn’t want to not be in the right spot,” Earls said.

“But now that we know what our defense is doing, we’re not thinking as much and we can fly around.”

Jake Fischer

Coach Mike Stoops says that Fischer was showing signs of becoming a potential impact player in the spring, when the junior suffered a torn ACL late in the final scrimmage.

Fischer’s status figures to be updated when Arizona begins camp, but a mid-season return seems to be the most optimistic outlook. Fischer has a redshirt season available.

Fischer, from Oro Valley’s Ironwood Ridge High School, played mostly on special teams as a true freshman before becoming a starter last season. His spot was often replaced by the nickel back, but Fischer saw ample time and made 58 tackles, including 7.5 for loss.

That kind of production put to rest concerns that his height (5-foot-11) would be a detriment.

Bilal Muhammed

Muhammed played on special teams last season after making the team as a walk-on from El Camino Community College in Torrance, Calif. Given the Wildcats’ attrition at the position, he’s in line for key time at linebacker if he can continue to build off a good spring.

His year of experience in the program will help as he tries to hold off freshman newcomers Rob Hankins, Hank Hobson and Domonique Petties (who is working through some NCAA Clearinghouse issues).

Another possibility is SirThomas Jackson, who, according to various reports, is expected to arrive as a walk-on this fall. He was an all-state defensive end at Seattle O’Dea High School, projecting as an outside linebacker in college.