The Vikings defense that took the field Friday may have been better than last year's division-title winner.

Linval Joseph, Sharrif Floyd, Harrison Smith and Anthony Barr were together. Relatively healthy. Staying that way is just one critical element for this promising Vikings team to push farther than last year's first-round playoff exit.

"I think it's really important," Floyd said. "All of our starters playing as a unit together is a sight to see."

Between five stars, including Everson Griffen, the Vikings lost 14 combined starts last year on defense, which has served as the backbone for the franchise's turnaround under head coach Mike Zimmer. They all returned to the field at the start of training camp — a step in the right direction after Floyd and Barr were held out of many workouts this spring.

"I missed it," Barr said. "When it's taken away from me, you appreciate it a little bit more."

Toughness isn't something wisely questioned of professional football players. Yet they're held to perhaps the highest standard in American sports. Last year, Barr played through a broken left hand that limited him from even putting his shirt on by himself. Barr, who was still a Pro Bowl alternate, eventually sat for much of three games because of a groin injury. Floyd has missed nine starts in the past two seasons, forced out of four starts last year because of a midseason operation to remove cartilage from his knee.

Floyd wore a brace on his left knee during Friday's practice.

"So far, so good," Floyd said. "If it was bothering me, I wouldn't have been able to do any plays. It's just building strength, that's pretty much it."

Patterson exits early

After making a leaping downfield grab over cornerback Jabari Price, receiver Cordarrelle Patterson's first reaction was to knock his own helmet in frustration.

Patterson landed hard on his left shoulder and walked off with athletic trainer Eric Sugarman. A brief look in the team's medical tent ended with Patterson exiting the field for good.

"He made a great catch and it wasn't his left hand or wrist, I can tell you that," Zimmer told KFAN immediately after practice. "I don't think it's anything concerning, but they're taking a look at it."

Patterson, 25, is trying to earn a new contract this season as he enters the final year of his rookie deal in Minnesota. He's worked primarily with the second-team offense and backup quarterback Shaun Hill, who threw the pass on the play.

Peterson eases in

Adrian Peterson is known for his hard-core training regimen that has helped keep the 31-year-old in peak physical condition.

So the Vikings are easing him into camp after he "tweaked himself" this summer, Zimmer told KFAN. Peterson took the Vikings' conditioning test on Friday, a day after his teammates, and was seen jogging on a side field under the supervision of Sugarman.

Peterson did get some light work in with the top offense and Teddy Bridgewater, though not during full team drills.

'As soon as possible'

The offensive line competition begins in earnest Sunday when Vikings players don pads for the first time since January.

Only then will Friday's top lineup of Matt Kalil, Alex Boone, John Sullivan, Brandon Fusco and Andre Smith be challenged. Pinning down a starting five and growing continuity will be a crucial task for the Vikings this preseason. It's one Zimmer hopes to establish as soon as the worthy players prove themselves.

"As soon as possible," Zimmer said of picking a starting offensive line. "But it may be this week, it may be next week. I don't know. It's really about when we've made the decision that this is how we want it to go. We still have some combinations we want to look at."