There are few certainties in life, but you'll get pretty close to one if you bet that Hope Solo will play every minute in the Olympics this summer. Just like she did in the World Cup last summer. And in London 2012. And in the 2011 World Cup. And in Beijing 2008.

At some point, that streak has to end. But goalkeepers age better than outfield players, and Solo has been among the very best at her position over the whole course of her career. So while change will come some day, there's never been much reason to think ‘some day' was anytime soon.

But maybe, just maybe, we're starting to get a little closer. To be clear, while Solo no longer dominates the area quite as much as she once did, she remains a world-class keeper by any measure. It's just that the US is blessed with Alyssa Naeher and Ashlyn Harris, who are world-class in their own right. And based on the evidence of the first quarter of the NWSL season, Solo might need to start looking over her shoulder a little bit. Naeher and Harris have both been excellent--2nd and 3rd in the league in saves--and have managed this record against stellar competition.

Naeher let in three goals in the opening week, but you'd be hard-pressed to fault her for any of them. In fact, her heroic saves were all that kept Chicago's shambolic defense from a far more embarrassing result. And since then, she recorded four consecutive clean sheets, chipping in a few excellent saves along the way, but also playing a key role in marshaling and organizing a defense that often looked disjointed last year.

Her saves aren't often stunning (though take a look at the highlight reel for week 5 and you'll see some stunners), but that's not really her game. She's more about proper positioning and sureness of touch. Once she closes down the space, the ball is hers and the attack is over. She's also an excellent decision-maker, coming off her line decisively when necessary and rarely getting trapped in between thoughts. These strengths were already clear enough during her time with the Breakers but have become even more obvious now that she's supported by a more solid defensive unit.

Meanwhile, down in Orlando, Ashlyn Harris is making a case against her recent relegation to third-choice for the national team. While she does have some weaknesses in positioning, which can sometimes invite pressure, her reaction time and shot-stopping abilities are top quality. And that's been on great display this year. For an expansion team to emerge from matches against Portland, Houston, Chicago, and Seattle only having conceded four goals is genuinely impressive. And Harris has been a huge part of that equation, providing spectacular saves of every sort.

Reaction saves, through traffic:

Closing down attackers who are through on goal:

Leaping tip-saves:

These efforts have won her the ‘save of the week' three times in four weeks so far. And while there's some reason to doubt the full scientific validity of that particular contest, the saves have been very good.

Contrast those performances with Solo's on the season's opening week, when the Reign lost in somewhat shocking fashion to Sky Blue. On the first goal, she shaded too far to her right and then overcommitted to the near post once the cross came in. It wasn't a glaring error, but she'd certainly expect herself to do more. And the second goal was even more egregious. It began with bad distribution, giving the ball away and putting her team unexpectedly back on the defense. Then, she inexplicably and somewhat lackadaisically hugged the near post, seeming to think the ball would go out. But once the cross went over her head, the whole goal was wide open. You can watch both goals in the highlights. Kai's starts at 1:22 and the buildup for Conheeney's starts at 4:21.

And it's not just her responsibility for those goals. As Dan Lauletta noted: "With the possible exception of 2013 when she was recovering from wrist surgery, have we ever seen Hope Solo play worse than she did on Sunday?"

Of course, it's silly to dwell too much on a single game. Anyone can have a bad day. And Solo has generally looked her old self since then, earning two clean sheets (albeit without much for her to do) and turning in an excellent performance against Orlando in week 4 to keep the scoreline close. So let's not carve any epitaphs quite yet. The occasional misstep aside, Solo is probably still the best keeper in the world.

But it may not be too long before we enter a period defined more by real competition for the top slot. And given the lull between the Olympics and the 2019 World Cup, there's a real chance that this summer will be the last time she's the #1 going into a major tournament.

On the other hand, it's probably never a good idea to bet too heavily against Hope Solo. So we may just have to wait and see how it shakes out.