With a no-nonsense look etched on her face, Ada Hegerberg stares straight into the camera and says: "Now it's time for action."

It's fitting the Norwegian superstar was chosen as the face of a recently launched campaign aimed at improving the profile and standards in women's soccer.

Not just because, as the first ever female winner of the Ballon d'Or, she is the outstanding player in the women's game.

But because she also is fighting her own private battle for equality and greater respect in the sport, a battle that will deprive soccer fans of the chance to see her at the Women's World Cup, which kicks off in France on June 7.

Hegerberg hasn't played for Norway for two years, ever since she decided to rule herself out of selection over what she perceives to be a general disregard for women's soccer in the country. The crux of her frustration is the uneven pace of progress and strategy in the women's game.

The Norwegian Football Federation has reached an agreement with Norway's players' association for an equal pay deal between men and women. The deal, struck in December 2017, was held up as the first of its kind in international soccer.

The federation also now has a female sporting director — former international Lise Klaveness — who splits her time equally between the country's men's and women's teams, and runs a project aimed at developing top women's coaches. She is sure Norway invests more money in the women's game than "most other federations."

Still, Hegerberg won't return for the World Cup.

"A lot of things need to be done," she said in an interview with The Associated Press last year, "to make the conditions better for women who play football."

Norway coach Martin Sjogren said meetings were held in an effort to change Hegerberg's mind ahead of the tournament. They were in vain.

"As a coach, you need to focus on the players who want to be a part of the team," Sjogren said, "and Ada doesn't."

Klaveness doesn't want the dispute with Hegerberg to leave a cloud over the Norwegian team but was keen to stress she has "not given up" on the country's star player.

"We need to try to have a confidential relationship and just talk directly to each other so we can have common ground and maybe have her back after the World Cup," Klaveness said in a phone interview with the AP. "That's where we are now."

And so, the best player in women's soccer won't be gracing the biggest tournament in women's soccer. It's a black eye for FIFA — the organizer of the World Cup — considering Hegerberg won the Ballon d'Or last year and stood alongside Lionel Messi, the winner of the men's award, as the current icons of the sport.

She is putting up Messi-like scoring numbers, too.

Thanks to her hat trick for Lyon in its 4-0 win over Barcelona in the Women's Champions League final , she has 44 goals in 46 appearances in that competition. In domestic games, she has 211 goals over 208 games.

Her goal tally for Norway — 38 in 66 appearances — is also extraordinary, considering she stopped playing for the team at the age of 21.

That's why she'll be so sorely missed in France.

"I think Ada's decision needs to be respected," Nadine Kessler, UEFA women's football director, told the AP. "It's a brave decision to consciously miss a World Cup."

That Hegerberg saw fit to front a campaign by UEFA entitled "Time for Action" that was launched a month before the World Cup brought further exposure to the fight for greater equality. The United States women's team, in particular, has been at the forefront of that.

American players have filed a federal discrimination lawsuit against the U.S. Soccer Federation over equal treatment and pay. The players allege ongoing "institutionalized gender discrimination" that includes unequal pay with their counterparts on the men's national team.

Unlike Hegerberg, the U.S. team won't be boycotting the World Cup, but the discontent is simmering there and elsewhere.

Over the last couple of years, Ireland's team has threatened to go on strike, while Denmark's team canceled a World Cup qualifier against Sweden because of a pay dispute, leading to its players eventually signing a four-year collective bargaining agreement with their federation.

There clearly is growing momentum behind the women's game — for example, the $13 million sponsorship deal secured by the Women's Super League in England, the record crowd of 60,739 for a women's match in Spain, and the record attendance of 39,000 for a domestic league match in Italy — and it is helping to establish players like Hegerberg as household names.

So while her absence from the World Cup is a loss for fans, her ongoing fight for change could reap benefits for the game in the long term.

"We are happy for this debate to raise attention and respect for women's soccer in the world," Klaveness said, "and I do view it as a big change-maker. But I just wish she was in our team."