MANKATO — An old adage about people is they’re always harder on the ones they love.

This fits Mike Zimmer and Minnesota’s cornerbacks.

Zimmer coaches them as critically as any players on the Vikings, and if there were a contest held to determine his favorite position on the field the others would probably be fighting for second place.

“He is a hard coach, but that’s something that I enjoy,” said rookie Trae Waynes, the team’s first-round draft pick.

Here’s the important part about those high cornerback standards: The results Zimmer has coaxed from that group over the years have produced for him plenty of credibility on the subject.

With Dallas and Cincinnati as an assistant and now with Minnesota as the man in charge, Zimmer has presided over a lot of skill development at that critical spot.

“For what we do defensively, it’s an extremely important position. So it allows you to do so many other things if you’ve got the kind of guys you’re looking for and they’ll do what you want,” Zimmer said.

“A lot of it is just getting back and studying and trying to figure out the best way to teach and trying to get these guys the best position to be in. So I don’t know. I like it. I just like it.”

There’s a lot to like on this roster, for that matter.

Xavier Rhodes will pair with 13-year veteran Terence Newman, who has totaled six seasons of experience under Zimmer with the Cowboys and Bengals, in the base defense.

Captain Munnerlyn, one of last year’s big-money free agents who struggled to adjust to Zimmer’s system, is on track to be the slot cornerback in the nickel package. That ought to keep the pressure off Waynes, the prized prospect from Michigan State, as he picks up the professional game.

Zimmer’s voice cracked at the end of last season when remarking about the strides made by Rhodes, the team’s first-round draft pick in 2013. Rhodes has credited Zimmer often for his growth and improvement.

“I think Xavier’s had some success at some of the things that we’re trying to teach, and I think he appreciates that. Guys want to get feedback,” Zimmer said.

Josh Robinson, because of a pectoral muscle he tore during minicamp, has been on the physically unable to perform list with no indication he’s close to being cleared to participate in practice.

Another returning player at the position, Jabari Price, will miss the first two games of the season while serving an NFL suspension for a drunken driving arrest.

Setbacks such as these in seasons past would have been a lot more depleting. Now, Robinson, the team’s third-round draft pick in 2012, has become at best the fifth cornerback.

With Rhodes, Newman, Munnerlyn and Waynes, provided they avoid injuries and continue to improve in their execution of Zimmer’s scheme, the Vikings have one of the deepest groups of cornerbacks they’ve had perhaps in decades.

Over a 20-year span from 1994-2013, the Vikings were in the top half of the league in fewest yards passing allowed only twice: ninth in 1996 and 10th in 2010. They finished in the bottom third of the NFL in that category a whopping 14 times including next-to-last in 2006 and 2013 and last in 2007.

With Zimmer running the show last season, the Vikings were seventh in the league.

“I was locked into a system for five years and I was just so locked into that and I was like, ‘Man, I’d rather do it this way and see how it goes,’ instead of buying into his system,” Munnerlyn said. “But I’ve got to be all in. I’m all in, and I’m willing to learn and I think I’ve got it now.”