Camp Three-cap is a daily recap of three observations/things to know from Verizon Vikings Training Camp by Vikings.com's Mike Wobschall (@wobby), Craig Peters (@pcraigers) and the Vikings Entertainment Network.

Peters: Wallace vs. Rhodes Day 1

Vikings fans have been excited about the possible dimensions that offseason acquisition Mike Wallace can add to the offense and know the progress that Xavier Rhodes made last season in neutralizing opponents' top threats.

Training camp practices that are free and open to the public will offer fans that make it to Minnesota State University, Mankato to see the head-to-head contests between the speedy receiver and the aggressive corner. Rhodes didn't wait until Sunday afternoon's practice to show his competitive spirit. He nabbed a pair of interceptions in the morning walk-through.  

"I was about to say something bad, but it was great," Wallace said. "That lets you know that he's focused on the task at hand. He's focused on getting better and not letting anybody catch any passes. We're not going for that tomorrow. No picks tomorrow. We're going to bat it down, jump over the head, do whatever we need to do."

Rhodes had a sly smile when asked about the walk-through and said Wallace and Teddy Bridgewater "got a little upset about that, but I was just messing around with them."

As for the matchup with Wallace, Rhodes said it amounts to "speed."

"He's a guy that's very elusive," Rhodes said. "You don't think he's running, but he's running at top speed. He's great at doing that and at catching the ball too."

Wallace said he and Rhodes got together to run one-on-one drills in Miami during the break between organized team activity practices and camp.

"I always have fun going against Xavier," Wallace said. "We couldn't wait to get up to camp. We'll build our endurance. It's going to be a tough battle, but I'm going to win the battle."

The last player off the field because of the extra work he puts in with a passing machine, Wallace had been dropped off at the entrance to the fieldhouse but extended his day by walking over to sign autographs for fans.

Wobschall: Zimmer Optimistic on Linval Joseph's Second Season in Purple

Zimmer has met with reporters twice already at 2015 Verizon Vikings Training Camp and many of the questions being thrown his way are about new Vikings, such as Wallace and draft picks Eric Kendricks and Trae Waynes. On Sunday, though, Zimmer provided positive commentary on a player going into his second season with the Vikings – DT Linval Joseph.

Joseph was one of the team's big free agent signings a season ago and he played well in his debut season. But Zimmer expects bigger and better things from his space-eating DT. While rookies such as Kendricks and Waynes battle to assimilate into their new teams, Zimmer says it'll be players in the second season with the Vikings, such as Joseph, who will begin to reap the rewards of understanding what the coaches are asking of them.

"Almost always, the guy that comes in as a free agent into a new system, his second year is almost always much better than the first year," Zimmer explained.

"Honestly, he's looked very, very good in OTAs so I anticipate he's going to have a very, very good year. I'm tempered a little bit just because of the fact that we haven't been in pads yet and we won't get out there for a couple of days, but if he does the things that he's done in the OTAs and continues that way, I anticipate because he's a big, strong man, his body is in good shape. He came in at about 316 pounds, I believe, and he's a very, very good athlete."

Peters: Camp battles begin

We started the first **roundup** of camp activities with the Vikings decision to insert Mike Harris at right guard and taking an early lead in vying for the starting right guard spot created by the relocation of Brandon Fusco to left guard.

The Vikings also opened camp with an opportunity to become the starting middle linebacker. As they did during OTAs, Audie Cole and Kendricks worked the "Mike" spot.

"It's a spot that's up for grabs, and I just want the best guy to come in there and do what he needs to do," Zimmer said. "Audie made a lot of tackles against that last game against Chicago. His communication has improved tremendously from a year ago at this time, so that's part of it. I think he understands the defense much better now than he did a year ago and really the things that we're asking him to do. He just needs to continue to really carry on from where he finished – making plays, being physical, understanding the pass concepts and the pass games because that's such a big thing now for linebackers. It's not just playing the run anymore or the play actions. They need to understand where they need to be in the passing game."

Some believe the safety spot opposite Harrison Smith to be up for grabs. Robert Blanton, who started 13 games last season, saw the bulk of the action with the ones, but will continue to be challenged by Andrew Sendejo, Antone Exum, Jr., Anthony Harris and Shaun Prater.

In Case You Missed It

In honor of the Vikings **signing kicker** Blair Walsh to a contract extension Sunday and announcing it via its Snapchat account (vikingsnfl), here are three extra points from earlier in the day:

The Vikings have joined a short list of NFL teams to begin implementing **virtual reality technology**.

The **full transcript** of Coach Zimmer's session with media on Sunday.

The Vikings announced that Josh Robinson would open the preseason on the physically unable to perform list and other **roster moves** before their first walk-through.