There are a few things that can be known for certain. Canada, the Olympic champion, will not add a Women’s World Cup to its list of honors this year. Marta, the Brazilian star, will not end her career with the one international trophy that has eluded her. And Germany, somehow, managed to engineer its own exit despite winning its first game by six goals. Three superpowers, from three continents, are out.

At the end of two weeks, this World Cup has incontrovertibly delivered on its stated aim — to provide a stage on which women’s soccer’s simmering revolution might burst into life. That is about as far as the certainty stretches. Nigeria beat Australia. Colombia overcame Germany. The United States could not score against Portugal. Jamaica held France at bay.

That unpredictability, that sense of old hierarchies and longstanding orders being overturned on a daily basis, has illuminated the World Cup, of course. After 48 games — three quarters of the tournament — half of the teams have been sent home, and yet it feels as if the field of potential winners is broader than it was even two weeks ago.

In part, that is testament to the spirit, talent and organization of the teams — Jamaica, South Africa and Nigeria — that have gate-crashed what many had assumed would be a party for the richer nations of North America, Europe and Australasia. To some extent, though, it can be attributed not just to the strength of those new contenders, but to the weakness of the squads assumed to be at the head of the field.

The United States is, strictly speaking, still on track for a third straight world title. Australia, co-hosting with New Zealand, eventually emerged unscathed from its group. And most of Europe’s squadron of contenders — England, Spain, France, Sweden and the Netherlands — is present, too.

It would be an exaggeration, though, to suggest that any of them look entirely convincing. The United States was the width of a goal post away from group-stage elimination against Portugal. Vlatko Andonovski’s team has looked insipid in all three of its games. It has won only one, the first, against Vietnam. Against more polished opposition, the U.S. has seemed to lack both ideas and inspiration.

It has not been the most convincing start to the defense of its trophy, as several former members of the team — all working in the news media — have noted. Tobin Heath, Christen Press and Carli Lloyd have all offered a little friendly fire in the days since the United States’ scoreless draw with Portugal; their assessments, certainly, have been less glowing than those of the first lady, Jill Biden. That feedback may help to bind the squad together. It may have a galvanizing effect. It may not.

As they attempt to work through the team’s issues and find some sort of patchwork solution, Andonovski and his staff will take small solace in the fact that almost every one of the Americans’ peers and rivals has experienced similar teething problems. This year, few teams have been immune from the joyous chaos of the tournament.

Australia has lost its captain, its goal threat and its talisman — three roles, one Sam Kerr — and, until that demolition of Canada, it had started to show. It squeezed past Ireland and lost to Nigeria, all while seeming a little dazed and directionless in the absence of Kerr, who was supposed to be this tournament’s star.

If Kerr can recover from her calf injury, then the Australian become a formidable prospect. If she cannot, then it is hard not to feel they are just a little diminished.

A similar suspicion lingers over England, the reigning European champion. Sarina Wiegman’s team has won all of its games relatively comfortably. It sealed first place in its group with an ominous 6-1 victory, against China, the sort of win that might yet look like an omen by the end of the month.

The issue, though, is injury. England came into the tournament without several key players and has subsequently lost another, the Barcelona midfielder Keira Walsh. Wiegman, astute and pragmatic, has always managed to find solutions, but even her inventiveness would be tested should her resources thin any further.

Other teams do not even have the excuse of injury for their inconsistency. Spain started the tournament well, smooth and imperious, and then promptly lost heavily to Japan. France started poorly, held to a draw by Jamaica, but has slowly grown in stature, defeating Brazil and then sauntering past Panama.

There is an art to that, of course, a skill in gathering momentum as a tournament turns into the home straight. But then there is something to be said for serenity, too, and only two teams can lay claim to that state: Sweden, which sailed through what was admittedly a relatively kind group and now faces the U.S. in the round of 16, and Japan, which produced the performance of the tournament so far in picking apart Spain, both as a team and a concept.

A couple of weeks ago, both of those countries would have been regarded as respectable outsiders, the sort of teams that might pose a threat if they caught a break, if some of their more illustrious opponents fell by the wayside, if they could click while others sputtered. Now, it does not look like quite such a long shot to suggest one or the other might be able to stay the course.

It has taken 48 games to reach this point. Sixteen teams are gone. Sixteen teams remain. They will all have seen enough, experienced enough, to believe there is very little reason to rule anything out. There is very little that can be known, even now. The Women’s World Cup has reached that point when it becomes a smaller, more ruthless tournament. It feels, though, as if it is more open than it was at the start.