AT FIRST GLANCE it might seem that little could be learned from the U.S. women’s national team’s back-to-back blowout victories over Haiti this past week.

After the Australian national team pulled out of the friendlies at the last minute due to a collective bargaining dispute, Haiti, with a roster of amateurs and semi-professionals, essentially did the U.S. a favor by stepping in to take their place. At the same time, with the Australians ranked ninth in the world and the Haitian’s ranked 63rd, a massive drop-off in quality was not really that much of a surprise.

While the Americans throttled the Haitians by a combined score of 13-0, there was at least one interesting subplot that emerged as U.S. head coach Jill Ellis appeared to open up tryouts for the defensive center midfield position.

Since Shannon Boxx dropped out of the starting lineup following the 2012 Olympics, the U.S. has struggled to find a suitable replacement. For years, there was simply no one better at sitting in front of the U.S. center backs and providing cover than the venerable Boxx.

First, there was the ill-fated attempt to shoehorn Carli Lloyd into the position—a move initially made by former head coach Pia Sundhage—followed by Ellis’ less-than-ideal move to push Lauren Holiday deeper into the midfield and away from her normal attacking role.

Although both Lloyd and Holiday proved to be serviceable at the position, it was not a natural fit for either player and the U.S. found itself struggling on both the offensive and defensive ends during rough patches in 2014 and 2015.

Even in the early rounds of the World Cup this summer, the U.S. struggled to find its footing until a yellow card suspension to Lauren Holiday in the knockout round turned out to be a blessing in disguise.

With little other choice, Ellis was forced to insert Morgan Brian into the starting XI. After Brian’s strong performance against China in the quarterfinals Ellis moved away from the team’s 4-4-2 alignment and shifted to a 4-5-1. The three-player midfield featured Holiday and Brian holding with Lloyd pushed into the attacking midfield role.

That change unlocked the American attack. Lloyd thrived playing closer to goal, leading the U.S. to a win over Germany in the semifinals and then scoring a hat trick in the lopsided win over Japan in the final.

Ellis will not be able to reprise that winning formula when the U.S. plays in its next major tournament—the 2016 Olympics in Rio—because Holiday has announced she will be retiring at the end of the tour. Just months after finally solving her team’s offensive woes, Ellis is now facing nearly the same midfield dilemma she had before the World Cup because there is no one on the current U.S. roster who is a natural replacement for Holiday.

While the obvious solution would be to target a new player to fill the void at holding mid—and there several viable options in the NWSL—the move is complicated because of Olympic roster rules.

The U.S. will only be able to bring 18 players to Brazil, five fewer than the 23 players that traveled to Canada for the 2015 World Cup. And while some room will be opened by a few retirements—Boxx, Holiday, and Lori Chalupny (who is a bona fide holding midfielder herself) have all announced they are hanging up their cleats—those Olympic roster rules put Ellis in a difficult position.

With Crystal Dunn pushing hard to make the roster, it already looks like Ellis will have to cut at least two of the team’s World Cup veterans for Rio. The odds that she would cut a third to make room for a newcomer to fill the holding midfield role seems unlikely, especially considering Ellis’ history of consistency in her roster choices.

Of the remaining players currently in the U.S. pool, that leaves Lloyd, Tobin Heath, Julie Johnston, and Becky Sauerbrunn as options to fill the hole that Holiday will leave—and none of them are ideal.

Considering that Lloyd’s offensive explosion in Canada coincided with her being moved closer to goal—and the fact that Lloyd has scored 14 goals in the United States’ last six matches—moving her deeper into the midfield is highly unlikely.

Heath also seems an odd choice for the position, but Ellis gave the idea a look in the first match against Haiti on Thursday night in Detroit. Heath certainly has the technical ability to play the position, but she is also a gifted attacker who loves to dance on the ball and take on defenders. That trait, while highly valued in her normal position on the wing, could prove to be a fatal liability in the center of the field, only one line ahead of the U.S. back four. Perhaps she could learn the position with time, but it seems like a longshot.

Tobin Heath giveaways? Nah, bro that never happens.

— Jennifer Gordon (@jgordon1987) September 17, 2015

That leaves Johnston and Sauerbrunn, who, oddly enough, might be Ellis’ best options for the role. But to move either into the position, Ellis would have to break up the dynamic central defense duo that kept the team afloat in the early rounds of the World Cup when the U.S. offense sputtered.

"I always want to do whatever senpai wants me to do." - JJ on Becky Sauerbrunn [paraphrased]

— thrace (@thrace) September 17, 2015

While Johnston has played almost exclusively as a center back for the U.S., including in the 2012 U-20 World Cup, she saw time as a central midfielder in her college days and would provide a strong physical presence in the middle of the field. She also told American Soccer Now in April that while playing center back was her main focus, she could handle the No. 6 role.

“I like to think that I can play both a holding mid spot and defender—I feel like I can play two roles,” said Johnston. “I do try and watch Lauren Holiday as well just to understand both roles. Whatever the coaches want, I'm willing to do. I don't think that, as a No. 6 right now, that's my main focus. I'm more focusing on what I can do to be a better center back."

Sauerbrunn also has a number of characteristics that would seem to make her an ideal candidate. She is an excellent 1 v. 1 defender, reads the game superbly well, is possession-oriented, and carries the ball forward with confidence. The downside, of course, is that she is considered by many to be the best center back in the world and Sauerbrunn told ASN last year that playing in the midfield would be a major change.

“There’s never been a serious discussion about me playing in the midfield,” Sauerbrunn said. “It’s such an important position and I haven’t played center mid in many, many years. It’s something I’d have to train at exclusively. I don’t know if I could do it at the international level. It’s a really tough job.”

Nonetheless, Ellis did give Sauerbrunn a look at the holding position in Sunday’s game against Haiti in Birmingham, Ala.

Somewhat surprised Ellis would experiment with Sauerbrunn in midfield today instead of Johnston. Still suspect Sauerbrunn can do well there.

— Grant Wahl (@GrantWahl) September 20, 2015

Despite the potential drawbacks of breaking up the Johnston-Sauerbrunn combo, one advantage of either of them playing the holding role is that it would free up Brian to be more adventurous going forward. Brian, like Lloyd and Holiday before her, is not a natural holding midfielder and can contribute to the U.S.’s offense. With a converted center back as her partner in the double-pivot, Brian would be free to go forward into the attacking third with confidence knowing Johnston or Sauerbrunn would be covering that space behind her.

If Ellis goes with either Sauerbrunn or Johnston, she will need to dig into her bench for another center back, but that is one area that the team does have depth. Still available is captain Christie Rampone, to say nothing of Whitney Engen—who proved herself more than capable in the February friendlies against France and England.

Barring a newcomer getting called in and emerging as a legitimate option at the holding position, the U.S. simply has more depth at center back than the holding position. And while it may not be an ideal scenario, playing Johnston or Sauerbrunn in the midfield is probably the best option the U.S. has going forward.

John D. Halloran is an American Soccer Now columnist. Follow him on Twitter.