Iowa has built a prolific defense over the past two decades, and its going to be a challenge for the Michigan football team. Alum Becca Mahon/Daily. Buy this photo.

It’s a system older than every player that will take the field on Saturday.

Back in 1999, when Iowa coach Kirk Ferentz was hired to take over and rebuild the Iowa program, he brought with him a man by the name of Norm Parker. The two of them constructed the Hawkeyes around the identity of a defense-first football team. Now, 24 seasons — and 21 winning ones — later, that original vision is as prevalent as ever.

“It’s a system, it’s a way of playing,” Michigan coach Jim Harbaugh said on Monday. “It’s the Parker way, and it’s really good.”

Even though Norm is gone, the Parker way has continued in Iowa City. Phil Parker has been the Iowa defensive coordinator since 2011, and even though he shares no blood with Norm, Phil prays to the same football pantheon.

This season, the Hawkeyes follow that formula as much as any: They have the No. 1 scoring defense in the nation, allowing under six points a game.

Iowa’s defense doesn’t do anything that particularly jumps out at you. It’s neither flashy nor exotic; it’s just so good at what it does. Everyone is always in the right spot, knows their calls and tackles well. They don’t make mistakes, they don’t blow coverages and they wait for their opponent to stumble and then jump on them.

On Monday, Harbaugh gave the Hawkeyes defense its flowers for minutes on end.

“Everybody knows what to do,” Harbaugh said. “Everybody’s playing the proper leverage, the proper technique, the proper fundamentals at all times.”

He went on:

“If you’re not as sound as you can possibly be, then you’re in for a rough one.”

And on:

“(The) scheme is flawless, everybody (is) where they’re supposed to be, when they’re supposed to be, they’re playing the technique they’re supposed to be.”

What Harbaugh stressed, the reason he claims the Iowa defense is such a respected group, is that it forces opposing offenses to be as flawless as itself. That’s a tall task for most teams in the country, and it’s especially tough for a quarterback — sophomore J.J. McCarthy — who is making his third career start and his first on the road.

When the mistakes come, and against the Hawkeyes they almost always do, the Iowa defense swarms. That’s why it’s one of the best units in the country at taking the football away year after year.

This isn’t to say that Michigan has no chance against the Hawkeyes come Saturday. The Wolverines boast the No. 1 scoring offense in the country, and even though that number has been artificially inflated by bad opponents, it’s still indicative of Michigan’s offensive strength.

In fact, the Wolverines have the weapons to stress the Iowa defense. An explosive receiving core, an ultra-talented quarterback and an improving offensive line to go along with an obvious edge in talent.

But the Hawkeyes have a knack for neutralizing talent gaps with their skill and consistency — they are an alarming, unbelievable 5-1 in their last six games against AP top-five teams at home. Saturday’s game and whether Michigan finds success will probably come down to how many mistakes it makes and how costly those are.

If the Wolverines keep it clean and are as disciplined as they’ve been so far, though, there is the blueprint for success. Just look at last year. 

Many even think the Wolverines’ offense is more potent than last year’s group — a unit that put up 42 points on Iowa en route to a Big Ten title, bringing the Hawkeyes their first defensive falter of the season. 

This Iowa defense is different than last year’s, but only to a certain extent. The blueprint is the same — it has been since Norm — and the Hawkeyes are still of that ilk.

The tape is out on the Parker way, Iowa’s defense isn’t anything new. For the most part, Michigan already knows what it’s going to see on Saturday, but that’s only half of the equation.

The Wolverines still need to find a way to beat it.