The Raiders wrapped up their second day of training camp practice Saturday, and there was an added level of excitement with a select group of fans welcomed to the team's Napa Valley facility.

On the field, it was another step in a long process for first-year head coach Jack Del Rio.

"I thought it was a pretty solid day's work," Del Rio said. "So much to get done, but the energy was good. I think having a pretty good crowd out there was nice."

As the Raiders get set to turn things up a notch Sunday, here are some notes from Day 2.

Injury issues aren't serious

Rod Streater, Trent Richardson and, perhaps most notably, rookie tight end Clive Walford were out for the second straight day Saturday, while Sio Moore returned from the physically unable to perform list. Streater and Richardson are on the non-football injury list, so their absence was expected. Walford's status is a bit of a mystery, but Del Rio said it's nothing to worry about.

"We get one guy back, we'll get the rest of the guys back as we go here," Del Rio said. "I put them in a day-to-day category and just when I get them, (the trainers) say, 'Hey you got the green light coach,' I alert the staff and they're ready to go. Until then, we're just letting the trainers do their thing with them and making sure they're getting all the work they can on the side, things that won't bother whatever they have going on, and we'll be ready to roll soon."

Rivera makes early impression

Walford recently said he's aiming to be the Raiders' starting tight end come Week 1. Incumbent Mychal Rivera will have something to say to that, and he's already made a good impression on Del Rio with some impressive plays.

"Having gone against him, I know he's an athletic guy," said Del Rio, formerly the defensive coordinator for the AFC West rival Broncos. "I think he showed some of that athleticism early here in this camp with a couple nice catches. We like the way he's worked throughout the offseason. He's continued to strengthen himself and better himself as a player."

Corners are raw but promising

The Raiders are working with a young group of corners during training camp, with second-year players TJ Carrie and Keith McGill joined at the top of the depth chart by D.J. Hayden. McGill made a nice play by stripping rookie receiver Amari Cooper, according to The San Francisco Chronicle's Vic Tafur, who also singled out third-year corner Neiko Thorpe for having a nice day.

Del Rio has liked what he's seen from the unit but emphasized that it has a long way to go.

"We feel like we have a group there that has a chance to develop," Del Rio said. "Some young, talented guys -- physically talented guys -- that need work. So they're gonna get that. It's going to be a very competitive camp. We'll let them be developed, be coached, let them compete against each other and let the guys who are the most productive play the most."

Things get chippy

Training camp often brings out short fuses and quick tempers during the long, hot days. That was the case for a brief moment Saturday, when rookie guard Jon Feliciano and Shelby Harris got in a little skirmish towards the end of practice.

Minor dust ups like that happen at camps throughout the league, but Del Rio didn't seem thrilled about it after practice.

"I think (Feliciano) probably was doing a little too much holding or something," Del Rio said. "I think there were minor disagreements. The guys understand how I feel about it. We need to conduct ourselves in a way that we're all men out here. Sometimes it gets hot and you get irritated, but how you respond is important. So we're going to work hard to make sure we respond the right way."

The real fun starts Sunday

When asked about Feliciano and if he brings a sort of edge to the offensive line, Del Rio said it's hard to judge guys up front until players put on pads.

That moment comes Sunday, and that's when Del Rio and staff will get a true look at what they're working with on both sides of the ball.

"The game's played in pads, so you really can't get a full evaluation until you get your team in pads and see them compete," Del Rio said. "That's the next part, so we're excited to get that phase going, and that will be part of what we do."