By MATT DASILVA

The University of Northern Iowa’s McLeod Center in Cedar Falls has a sort of bandbox quality. Three thousand fans can sound like 10,000.
But the University of Missouri women’s volleyball players did not let the noise rattle them. Their five-set victory (25-19, 17-25, 26-24, 26-28, 15-10) over host Northern Iowa last week in the first round of the 64-team national tournament was the event’s biggest upset — an unseeded team beating a No. 5 — since the N.C.A.A. started seeding a portion of the field in 2000.

“Epic,” Missouri’s head coach, Wayne Kreklow, called it in a telephone interview. “It was so loud you could hardly hear yourself.”

Less than 24 hours later, the Tigers survived a scare to defeat unseeded Northwestern in four sets. “I compare it to coming off the sugar high and all of a sudden, you crash,” he said. “But we caught our second wind.”

With that victory, the Tigers advanced to Friday’s regional semifinals at Penn State, where they will face 12th-seeded Duke.

Underdogs again. It is a familiar, if not preferred, role for Team Kreklow. That is what the volleyball community calls Kreklow and his wife, Susan, who arrived in 2000 to take over a program that had drifted to the bottom of the Big 12. They came from across town, where as co-head coaches they had led Columbia College to N.A.I.A. championships in 1998 and 1999.

The husband-wife tandem wasted no time turning around the Tigers, who as recently as 1996 were 0-28. Under the Kreklows, Missouri posted three straight 20-win seasons (2000, 2001 and 2002) for the first time since the 1980s.

Their titles have changed over time. Susan Kreklow started as the head coach, with Wayne serving as associate head coach. They swapped positions in 2005 for more flexibility to raise their three children, the oldest of whom, Rick, is a freshman on the Missouri basketball team.

That 2005 season was the last time Missouri advanced this far. The Tigers fell just short of the national semifinals, losing to Tennessee in a regional final.

“I don’t think we really planned it,” Wayne Kreklow said of coaching with his wife. “It just kind of fell together.”

In 2007, Susan moved behind the scenes to become director of volleyball operations, which was difficult for her because it limited her courtside role. Otherwise, she said, the title changes are semantics.

“We do what we do,” she said. “Titles change to fit the role. Part of the reason it does work is because we work together. Coaching a Division I program has a lot of time demands. It’s not really a job. It’s a lifestyle.”

Wayne, a basketball all-American at Drake who won an N.B.A. title as a reserve for the Boston Celtics in 1980-81, met Susan when they played on the Midwest postcollegiate club volleyball circuit. Both were high school coaches and teachers at the time.

“They’re my parents away from home,” said Catie Wilson, a senior middle blocker. “They know how to win and how to coach us in a positive way. Wayne will be sitting there in a timeout telling us whatever we’ve got to do to win the game, and Susan will be there tapping him on the shoulder telling him, ‘You’ve got five seconds to get these girls back on the court.’ ”

The Kreklow family dynamic has evolved this season with the addition of the freshman setter Molly Kreklow, their niece, who graduated from high school early and enrolled at Missouri last January in part to try to preempt any misgivings upperclassmen might have because of her last name. Kreklow, from Delano, Minn., arrived on campus as the nation’s 20th-ranked recruit.

“One of the first things I thought about was I really have to establish a relationship with everybody and prove myself as a good player,” she said. “Give them anything to doubt, and they’re going to take that opportunity.”

Setters play the most visible role on the court. They control the tempo of the offense, and they determine which player will attack the ball or try to catch the opposing defense off guard with a dump for the kill.

With Kreklow setting, the Tigers have become more aggressive and efficient on offense, traits they lacked when they missed the N.C.A.A. tournament the last two seasons.

A dislocated right pinkie forced Kreklow to block with one hand and to serve underhand at the beginning of this season. The injury broke skin and required surgical insertion of a titanium pin, procedures she underwent with her aunt at her side.

“But I would have been there with any player,” Susan Kreklow said. “That’s part of what we do.”

Molly Kreklow’s setting has not suffered. She leads Missouri with 12 double-doubles in 32 matches and ranked second in the Big 12 in assists per set despite also playing with a stress fracture in her right foot that may require surgery after the season.

The outside hitter Julianna Klein, a fifth-year senior who had decisive kills in the third and fifth games of the upset of Northern Iowa, said that Kreklow stepped right in. “It was just seamless, her transition into our team,” Klein said. “It helps that Molly has been distributing the ball well among hitters. We’re all pretty happy.”

It also helped that Kreklow knew the coaches. But she tries to keep family matters separate.

“My roommate is a girl on the team,” Kreklow said. “I said, ‘Yeah, my uncle said. ...’ And she said, ‘You have an uncle that lives in Missouri?’ I was like, ‘Yeah, Wayne.’ It’s something I’ve tried to be careful with so people don’t get put off.”

Kreklow’s forthright approach on and off the court might be the best indicator that she is, well, a Kreklow. Her approach is similar to the one Wayne Kreklow said he took when he and his wife entered what he called the dog-eat-dog world of major college athletics and again as they have seen top-level programs invest more substantially in their sport.

“It was an opportunity to see if you could be successful at a really high level while still trying to operate with some character,” he said. “I wanted to prove you could be successful, still be a good person and account for people in the program — and maybe not be the cutthroat, win-at-all-costs kind of person that seems to be more and more prevalent as the money increases.”