With Alex Boone out at Vikings practice, Joe Berger again proves his value

Joe Berger is a 305-pound piece of duct tape that's coming in handy once again as the Vikings opened their three-day minicamp with a storm-shortened practice on Tuesday at Winter Park.

With prized free agent signing Alex Boone sidelined because of an undisclosed injury, the Vikings turned once again to Berger, a 12-year veteran and the team's third-oldest player at 34. One season after Berger earned high marks while starting all 17 games for injured center John Sullivan, the longtime backup lineman's versatility was displayed again Tuesday when he stepped in for Boone and lined up next to Sullivan at first-team left guard.

Vikings coach Mike Zimmer wouldn't say whether Boone will participate at all this week, but didn't sound concerned when asked how big a deal it was that his giant left guard was a spectator for the non-padded practice.

"Not too much," Zimmer said. "We'd like to have everybody out there. But it shouldn't be a big deal. He's a pretty smart guy, even though he went to Ohio State."

Defensive tackles Sharrif Floyd and Bruce Gaston and tight end Rhett Ellison also didn't practice. Linebacker Anthony Barr, nose tackle Linval Joseph and cornerback Mackensie Alexander went through individual drills only. Guard Mike Harris and linebacker Travis Lewis weren't at practice, which ended about 15 minutes early because of lightning.

By now, every Vikings fan is well-versed on Adrian Peterson's preference to run from traditional formations as opposed to the shotgun. But the perennial All-Pro also has vowed to increase his versatility at the not-so-tender age of 31.

Zimmer said he spotted two particular plays Tuesday that tells him Peterson is working hard to adjust his game to an offense that features new blocking schemes.

Even without Barr, Joseph and Floyd in the lineup, the defense clearly outshines the offense when the two sides compete in practice. Of course, that's to be expected since so few changes have been made to the defensive system that Zimmer brought with him in 2014.

"I think defensively we're playing very confident and relaxed, like they should be in the third year of this system," Zimmer said. "Offensively, we've added some different wrinkles that guys have been working real hard at in different techniques. Overall, it's been good."

One player who looks to be at midseason speed is defensive end Everson Griffen. His speed and assortment of moves are succeeding consistently and forcing left tackle Matt Kalil to play full throttle every snap.

Asked if he now considers himself the team's tone-setter, Griffen said, "I'm trying to do that. Come out here every day and show the young guys how to work. Our D-line group, we got to set the bar high. We have to go out there with the mind-set that we're going to be the best. If we can put this team on our back, we can go a long ways."

Want a subtle example of Zimmer's ability to command practice? Here you go:

After practice, Zimmer praised his players for how hard they work and how little he has to prod them. Most of the time.

"I just kind of watch them and how they go about their business and have a feel for it," Zimmer said. "Something happened last week. They were doing something I didn't like so I kind of told them about it. I think when you have good guys, smart guys, guys who care, you don't have to that a lot. But if they get out of line, they know that daddy's mad."