What we learned about USWNT in 2017 -- and what looms ahead?

Alex Morgan, right, led the U.S. women with seven goals in 2017, while Julie Ertz scored six goals, all on set pieces. AP Photo/Gerald Herbert

Questions lingered as little as three months before the 2015 Women's World Cup as to who should play next to Becky Sauerbrunn in the center of the U.S. women's national team defense. Julie Ertz provided a resounding if unlikely answer. Three games into the tournament, questions remained about how to spark the American midfield. A tactical switch freed Carli Lloyd to flourish.

Which is to say there will always be questions, right up until someone hands you a trophy. Or doesn't.

So roughly 10 months from the next attempt at World Cup qualifying, let alone the subsequent global event in France in the summer of 2019, it shouldn't set off alarm bells to suggest the U.S. team finished a year designed to search for answers with a legion of unanswered questions.

It was a year of discovery, but not so much of answers as what questions to ask next.

U.S. coach Jill Ellis told players after last year's Olympics that there would be open competition for a roster that had to get younger. She lived up to it. Including spillover from the final games of 2016, the tally for roughly the past 12 months runs to more than 50 players called into training camps and 30 used in games, including more than a dozen debuts ranging from active collegians to National Women's Soccer League veterans.

Before a recent game Megan Rapinoe only half-jokingly suggested the team was entering a new phase, if only because, in as many words, there wasn't anyone left in line to audition. Rapinoe, echoing similar sentiments of her coach, was right. Whatever the lines are that are yet to be written, this particular play is mostly cast.

Among the success stories are Abby Dahlkemper, Rose Lavelle, Casey Short, Taylor Smith, Andi Sullivan and Lynn Williams, all of whom went from debuts to names almost safe to write in ink for qualifying. Despite more limited minutes, Jane Campbell and Sofia Huerta might not be far from that list.

Holdovers, too, prospered in 2017, even as the team rode out some rough seas of results. Shifted by Dahlkemper's development, Ertz proved an enthralling presence in a defensive midfield role. Sam Mewis went from Olympic alternate to iron woman, matching Sauerbrunn as the first players to start every game in a calendar year for the United States since 2012.

Naeher is No. 1 in the net -- for now

One of the most pivotal questions posed by the past year involves what was among the most stable positions in 2017.

The last time a goalkeeper other than Hope Solo started in a major international tournament for the United States was the third-place game in the 2007 World Cup.

Put another way, Mallory Pugh was 9 years old the last time the U.S. women played without Solo.

The suspension imposed by U.S. Soccer in the wake of last year's Olympics long since served, Solo has made it clear she remains an active player, albeit one coming off shoulder surgery and currently unattached to a club. For its part, U.S. Soccer hasn't publicly closed the door on her. It likely won't ever feel compelled to do so in words, instead leaving roster selection to speak for itself. But it is ever more difficult to envision a reunion.

Alyssa Naeher played a greater percentage of the team's total minutes this year than any other U.S. goalkeeper at this stage of a cycle, i.e. the first year of the four years that culminate with the World Cup and Olympics in successive years. Hesitant to enunciate a depth chart last fall or even this spring, Ellis went at least that far before the team's finale.

"Right now would I put Alyssa as our No. 1?" Ellis said. "Yes, I would."

If it was an equivocal endorsement, it came after an equivocal audition. Naeher made a full extension save that literally saved the recent 1-1 draw against Canada. Her distribution was at times instrumental for a team that wants to play out of the back, a 3-1 win last fall against the Netherlands, subsequent Euro champions, among the best examples. All of that behind a retooled back line with only Sauerbrunn and Kelley O'Hara holdovers.

Yet Naeher also had forgettable moments, a howler against Brazil one of those instances in which she failed to replicate the air of authority that marked the position for years (not that Solo was immune).

Her summer interrupted by a quad injury, Ashlyn Harris made three starts for the U.S. women, while Campbell and Adrianna Franch, so good for the NWSL champions, appear more developmental prospects at this juncture. That she has a No. 1 right now only means Ellis has a decision to make about going all in on Naeher.

"The job for me is to make sure my No. 2 and No. 3 are pushing to be the 1 and also get experience, so that if we pick up an injury, we've got enough experience," Ellis said. "That's going to be the challenge for me as I look over the next year, in terms of where can I find minutes.

"And obviously then there's the form. If the form's not there, then I think the other two -- and even bringing [Franch] into the mix -- are going to be pushing hard for that 1 spot."

Training camp in January will offer more evaluation

Too little time on the field, by contrast, leaves questions for two players initially shining lights of the youth movement. Both Lavelle and Sullivan were revelations in early appearances, Sullivan as a composed distributor deep in the midfield last fall and Lavelle as an electric attacking presence this spring. But Sullivan's recovery from an ACL tear and Lavelle's hamstring injury kept them off the field through most of the summer and fall. Both remain in plans but missed out on a year of world-class challenges.

"What we're going to have to do in January is make sure that we give them opportunities, which they will have in our training environment, to assimilate very quickly and then see what they can produce for us," Ellis said. "Rose and Andi are both very dynamic players that I think can help us. That's where I consistently look at we're still 18 [months], two years away from a World Cup -- where could they be? ... I think they are two players I see as a bright spot in our future, and I will continue to invest in them."

To a lesser degree, Pugh endured similar bumps in the road. She gained valuable experience as part of the Olympic lineup and played far more than either Lavelle or Sullivan for the United States this year, but injuries took her off the field just as she appeared to be hitting top form.

Indeed, as much as Ellis talks about trying to now develop the nervous system for the skeleton already assembled, the ability to do so is somewhat out of her control when it comes to injuries. Even as the U.S. women found a comfort level with a 4-3-3 this year, they did so without Tobin Heath at all, Morgan Brian hardly at all, and without Lloyd and Alex Morgan for stretches.

There is little reason to worry about the ability of those veterans (see Morgan's goal scoring upon her return or Lloyd's stellar play in the Champions League). But if the pattern is repeated next year, be it for those or other players in what is likely to be another long year of international and league obligations, a reconstructed team figuring out how to play as a collective entity could be problematic.

"If I look at 2015, we didn't really absorb a lot of injuries," Ellis said. "We didn't have a lot of people missing. And I think because we had a lot of time with [the national team], 2016 was similar. 2017 was the first year that our players truly played maximum for us and maximum for their NWSL teams. It's not a matter of which environment, it's a matter of the demands now on them physically and traveling. So we've absorbed a lot more injuries."

And what of an absentee of a different sort? That Crystal Dunn was missing for the final games against Canada because of obligations to Chelsea was an apt conclusion to a year when the United States appeared to move no closer to figuring out how best to make use of her considerable skill on the field.

That the team moves on from its year of discovery with as many questions as answers doesn't mark 2017 a failure. But it means 2018 will be busy.