PARIS -- France and the United States will soon be on opposite sides of one of the biggest games in the history of women's soccer. The two most abundant fan bases in this tournament will turn the Parc des Princes into a seething cauldron of nearly 50,000 voices, a "s---show circus" of epic proportions, as Megan Rapinoe giddily and memorably phrased it.

But before the World Cup co-favorites were rivals standing in each other's way of advancing to the semifinals, each had help from the other to make Friday night a reality.

Beyond emerging as a rival the U.S. needed, France has been a place to find professional advancement for numerous American players.

And for France, most of all captain Amandine Henry, living and playing amid and alongside her American peers offered a chance to study what sets them apart as three-time world champions.

"I think that's part of the beautiful game," Tobin Heath said Wednesday. "It's kind of this special relationship that happens in football, where you get kind of influenced by the people around you and the different cultures around you and it allows you to grow and develop."

Growth was part of what brought Henry across one ocean and nearly to another to play for the Portland Thorns in the National Women's Soccer League in 2016. Henry was compensated well for her time, but as reports that continue to place her near the top of the pay charts for Lyon make clear, she didn't need to leave home to be among the best earners in the women's game.

Tobin Heath is one of a handful of American players who've spent time playing professionally in France. Marc Atkins/Getty Images

What Portland offered was a look inside the American mindset, both alongside national team players such as Heath and Lindsay Horan on the Thorns and in a league that is defined by its balance.

"It is something I want to discover, the mentality of the Americans, because I am very impressed with the Americans when they are playing national teams," Henry told FourFourTwo at the time of her move in 2016. "Even if they are losing, they are going to fight until the last second to draw or win the game. They never give up and that is very impressive. They are really warriors. We have to learn that, and if I can bring that to the French national team, I will be happy."

France didn't play particularly well against Brazil in the round of 16. It didn't produce a bevy of scoring chances or dazzle with its passing. It struggled to put away a resilient opponent -- unable to do so in 90 minutes and in danger of placing its fate at the whim of a penalty shootout. Yet the team that won over fans with its bold play in the 2011 World Cup and 2012 Olympics, while also always finding a way to come up short in the biggest moments, didn't buckle under pressure.

A surge forward in extra time ended with Henry throwing her body at a pass to produce a sensational goal that finally saw off the Brazilians. It was downright American in its ability to rescue success from nearly two hours of imperfection.

Along with the advantages of playing at home, and a wealth of young talent, a positive mentality is one reason many made the French favorites entering the World Cup. That list included U.S. captain Megan Rapinoe, who played for Lyon in 2013 and at least jokingly took some credit for leaving an American imprint on the club team that is the core of the national team.

"I don't think there have probably been a lot of players personality-wise -- I'm definitely different from most of the French players, that's for sure," Rapinoe joked before the tournament. "So I think I brought a bit of lightness to them that they're probably missing every day."