EUGENE, Ore. (AP) — Ever since a track coach named Bill Bowerman tinkered with the idea of pouring rubber into his waffle iron to concoct a better shoe sole for running, Nike and the sport of track and field have become inseparably intertwined.

The results of much of that interconnectedness is on full display in the college town of Eugene — which is where Nike was founded and underwrites virtually every facet of sporting life at the University of Oregon. This week, the university is hosting the track and field Olympic trials. Next year, the sport’s world championships — the biggest event in track this side of the Olympics — take the stage.

Though frequently scrutinized the way any market leader is, Nike’s command of this sport has been tested over the past few years, both in its dominant position involving sponsorships with track’s top names, and also in the way it is perceived by its most fervent fans and critics.

Gender equity battles have led to the defection of several high-profile women runners, including nine-time Olympic medal winner Allyson Felix; a complex doping case involving Nike’s most high-profile coach, Alberto Salazar, continues to play out this summer at the Court of Arbitration for Sport; Nike’s role in developing new boundary-pushing technology for long-distance running shoes has garnered its share of sideways glances.

Meanwhile, virtually every major executive and organization in the sport — among them, USA Track and Field, and its president, Vin Lananna, and World Athletics president Sebastian Coe, and former USATF head Craig Masback — either has, or once had, some strong connection to Nike.

“You think about all they’re supporting — the jobs, the kids, the futures, and it’s a tough situation because, yes, they are doing good things,” said Kellie McElhaney, who teaches about diversity, equity and inclusion in the corporate world at Cal-Berkeley. “But any time any one organization is so deeply dependent on one source, whether it’s a person, or a company, it’s a dangerous model.”

The connection that might best illustrate the interdependence of Nike and its running partners is the 23-year sponsorship deal worth a reported $500 million the company cut with USA Track and Field in 2014. It was widely criticized in some corners: Some complained it gave Nike too much power over the sport. Meanwhile, USATF CEO Max Siegel took heat for underselling track’s growth potential with an arrangement that spans 2017-2040.

Siegel insisted it set the most sprawling sports operation in the U.S. Olympic space on sound financial footing for the long-term. When the COVID-19 pandemic hit and other U.S. Olympic sports organizations struggled, some of them even going bankrupt, USATF remained stable, in large part because of the Nike deal.

But Siegel does not adhere to the idea that USATF is beholden to its top sponsor.

“There’s a lot of conversation over the years about whether they have influence over our decisions,” Siegel said. “We’re an independent organization and they handle their matters. They don’t consult with us about internal things in our operation.”

In 2019, the link between USATF and Nike came under more scrutiny after the company received backlash for its policy of scaling back the contracts of female athletes after they became pregnant.

Over the span of a few months, high-profile runners such as Felix and Alysia Montano went public with soul-baring details about their Nike deals, which essentially lowered their earnings when they became pregnant.

Nike changed its contract terms. In 2018, it had waived so-called performance reductions for 12 months. A year later, it expanded the policy to cover an additional six months.

“We want to make it clear that we support women as they decide how to be both great mothers and great athletes,” said Nike spokeswoman Sandra Carreon-John.

But for some, it was too late.

“When I was with Nike, it was family this, family that, this is the Nike family,” Felix said in a recent interview in The New York Times. “You feel that that’s real, and then you see the other side of things, and it’s completely different.”

This week, Felix announced she is starting her own brand, Saysh, and is running in a spike made by the company. Other female runners, such as Tianna Bartoletta and Colleen Quigley, have also left Nike after what they’ve described as discriminatory or insulting business practices.

“Nike was trying to offer me less than what they offered me when I came out of college,” Quigley said in a recent podcast. “To me, it was just a slap in the face.”

And yet, Nike still sponsors an expansive roster of women. In track and field, that includes Sha’Carri Richardson, Vashti Cunningham and Elise Cranny, all of whom won U.S. titles and trips to the Olympics last weekend. Two of the world’s highest-profile female athletes also work with Nike: tennis players Serena Williams and Naomi Osaka.

The company has won awards for an understated and powerful ad featuring Colin Kaepernick that cut to the core of the current conversation about racial and social justice in this country.