Little did some guys know when watching “Hard Knocks” they were seeing a preview of their 2014 training camp.

Several Minnesota players recall details of then-Cincinnati defensive coordinator Mike Zimmer leading players through drills in the hot sun at Bengals camps featured on the HBO show in 2009 and 2013. Now, Zimmer is about to start his first camp as the Vikings’ head coach.

“I remember seeing those competition drills that (Zimmer) had,” linebacker Jasper Brinkley said. “It was just one-on-one to see who was the toughest. It was a man whooping a man.”

Yes, the Vikings got a feel for what Zimmer was all about during minicamps and organized team activities in the spring, but as Brinkley noted, that’s not the same as training camp.

“We were running around in shorts,” Brinkley said. “Now, when we go full pads, you’re going out there and you can’t hide.”

Vikings players report to camp in Mankato on Thursday, with practices starting Friday. Full pads will be donned Sunday, when the real action starts.

“I assume it’s going to be a pretty physical camp, just because of the reputation (Zimmer) has around the league,” said fullback Jerome Felton. “He’s kind of an old-school, no-nonsense guy and he wants to have a physical team. I would expect him to carry that into training camp, but that personally fits my game.”

Training camp’s primary story thread will be the competition at quarterback. Matt Cassel is the front-runner to start the opener Sept. 7 at St. Louis but will be pushed by rookie Teddy Bridgewater, and offensive coordinator Norv Turner insists Christian Ponder is in the mix, as well.

Plenty of eyes will be on Adrian Peterson, too, as he prepares to play his final season before turning 30 — the age at which many NFL running backs quickly go downhill. The eight-year veteran will show for his first training camp as a married player, having recently gotten hitched to longtime girlfriend Ashley Brown.

Yet perhaps Zimmer’s most important task will be rebuilding a defense that ranked 31st last season in yards allowed and 32nd, dead last, in points allowed under former coach Leslie Frazier. While the Vikings could end up having the same 11 offensive starters as they did in December, the defense will feature some new starters — three on the defensive line alone.

Gone are end Jared Allen and tackles Kevin Williams and Letroy Guion. Everson Griffen, Sharrif Floyd and newcomer Linval Joseph are expected to move into those spots.

Cornerback Captain Munnerlyn, another newcomer, hopes to move into the starting lineup. And Brinkley, who played for the Vikings from 2009-12 before playing last season in Arizona, is “very confident” he’ll reclaim the starting middle linebacker job he had in 2012.

The Vikings finished last season 5-10-1 but went 3-2-1 over the last six games of the season. And after getting a taste of Zimmer during spring drills, they’re optimistic about the progress they can make this season.

“We were in the playoffs (in 2012),” said linebacker Chad Greenway. “We know we can get right back there again. … There’s no doubt we can get back.

“I think the foundation was set with this offseason. It’s probably one of the better offseasons I’ve been around, just as far as intensity, the atmosphere of practice, the way (Zimmer) presents himself as a coach and what he wants from his players.”

Follow Chris Tomasson at twitter.com/christomasson.