As Adrian Peterson watched tape of Norv Turner's offenses from San Diego and Cleveland, it didn't take long for him to realize his role was going to be a little different in Minnesota's new offense.

The running backs in those offenses, from LaDainian Tomlinson to Darren Sproles to even little-known Chris Ogbonnaya, were all targeted often by their quarterbacks.

"I'm definitely going to be involved more in the passing game," Peterson said Thursday as the Vikings wrapped up their three-day voluntary minicamp. "They would always find a way to get the running back out in space. So I knew once we hired him that would be something that would be new for me. I'm pretty excited about that."

Peterson has piled up 10,115 rushing yards in seven seasons with the Vikings, but he has just 206 receptions for 1,697 yards and five touchdowns. He caught 69 passes over the past two seasons. His best season as a receiver came in 2009, when he set career highs with 43 catches and 436 receiving yards.

While defenders can attest to the kind of damage Peterson can do when he gets the ball in the open field, his big mitts have dropped 13 passes the past four seasons, according to Pro Football Focus.

Peterson is "a little bit" eager to prove he can be a consistent threat as a receiver, but he also said, "I've been in the league for eight years and I've caught all the passes."

Peterson said it will take time to learn Turner's offense and its foreign terminology. He likened practicing the new plays to "performing heart surgery without having a license," but he likes the team's direction.

He estimated that he is at "80 percent" after groin surgery in January.

"I have no doubt that when the season comes around I'll be ready to roll," Peterson said.

The 29-year-old isn't sure if the Vikings will draft a running back next week to lighten his workload, but he welcomes the help.

He also suggested that getting more touches in the passing game — he mentioned "eight to 10 catches" a game — as opposed to being a between-the-tackles battering ram could keep him fresher.

"The rushing yards might not be up to par, but it's not about that," he said. "I'm trying to win a championship, so if that's taking less of a pounding and being more productive in the passing game, I'm all in for it."

The more the merrier?

Chad Greenway is penciled in as the starter at one linebacker spot, but the other two spots are up for grabs among a crowded group of linebackers. Jasper Brinkley and Audie Cole worked with the first-team defense during Wednesday's open practice.

"It's a good, young group and it will be interesting to see where things fall," Greenway said.

The Vikings could also draft a playmaking linebacker next week — maybe even in the first round — and Greenway says a rookie would be welcome, too.

"Anybody that can help us win is obviously good for us," he said.

Sanford ready

Safety Jamarca Sanford was happy to get a glimpse of Zimmer's defense, which he said uses more coverages — he mentioned quarters (Cover 4) in particular — than the Cover 2 that former coach Leslie Frazier preferred.

And communication in the secondary will be key with new terminology being learned.

Sanford knows he must convince the new coaching staff to keep him in the starting lineup. The Vikings added veteran Kurt Coleman to the safety mix and could also address the position during the draft.

"I'm used to it," Sanford said. "The cream always rises to the top."