When it comes to explaining how the Gophers defense morphed from porous to near-impenetrable in just a year, logic fails.

Even coach Bob Motzko couldn't find a tangible answer.

"There's some chemistry there," Motzko said. "There's some magic going on in there."

Whether scientific or mystical, the result is the same. This incarnation of the Gophers D-unit is excellent, helping the team rank second in the nation in scoring defense, allowing just 1.58 goals per game, and third in scoring margin, outscoring opponents by two goals per game.

It helps a lot, of course, that goalie Jack LaFontaine is playing so well as a senior. His save percentage of .955 is the third best in the nation.

Only in the past three games have the Gophers allowed anything more than two goals in a matchup. That could be something of a second-half phenomenon with more teams dissecting what makes the No. 1 Gophers so staunch. That might have also led to the 11-1 team taking its first loss at Wisconsin this past Saturday. But at home against Notre Dame this weekend, the Gophers are looking to stem that slight skid.

"Everyone can do it all," freshman defenseman Mike Koster said of his defensive teammates. "… We just blend really well together. And guys can play with different people. So we can dress seven, eight, nine D. We've got a lot of depth."

That's abundantly clear. The Gophers had the unique honor of placing three defensemen on the recent gold-medal-winning U.S. World Juniors team. Freshman Brock Faber, sophomore Ryan Johnson and Jackson LaCombe returned shortly before the most recent Wisconsin series. Though the defense didn't dip in their absence, with players such as Koster stepping up in their steads.

LaCombe and Johnson are both high NHL draft picks from the second and first round, respectively. Plus, the Gophers have 14-year NHL veteran Paul Martin as an undergraduate assistant on the coaching staff. Between LaCombe and Johnson staying late at practice to help their teammates and Martin offering his pro experience, the Gophers defense never has a questioned unanswered.

And the defensemen ask a lot of them.

"That's kind of the biggest thing that I've noticed," said Martin, a former Gopher now finishing his degree. "… They have a great attitude, they come to work every day, and they ask questions, and they stay after to work on things. And it seems like they all get along, which is huge."

In Motzko's first two years as head coach, the Gophers allowed 2.84 and 3.27 goals per game. Trimming that to just more than 1.5 shows how different this defense is, even with some familiar holdovers such as Robbie Stucker, Ben Brinkman and Matt Staudacher.

"It came together very quickly," Motzko said. "And we're much more offensive than we've been. … The defending part of the game comes really naturally to this group. And our offense, we're still just scratching the surface where this group can go offensively."

Johnson has six assists in just eight games, while Koster has two goals and five assists. And when one of the defensemen scores or blocks a shot, teammates are eager to share in the excitement.

"Always being happy for each other and being supportive of each other," LaCombe said, adding the defense has forged strong off-ice friendships. "… Teammates will pat you on the back or whatnot. And I think we have that, so that's really awesome to see."