It's a weird time for D.C. United to be playing FC Dallas. MLS is sort of closed for the weekend, with just three games going on during the current window for international matches. United is feeling it, as Steve Birnbaum will be with the USMNT for their games against Guatemala. Alvaro Saborio will be with Costa Rica as well, likely opening a spot on the bench for someone like Miguel Aguilar.

For Dallas, the call-ups have left them in a very slightly larger bind:

Acosta, Zimmerman, Hernandez, Gonzalez, Akindele, Harris, and Figueroa all out for DC. (call-ups)



Stunning test of backline depth — 3rd Degree (@3rdDegreeNet) March 21, 2016

Let's go over this from the positions Dallas just got weaker at. Kellyn Acosta is a defensive midfielder who can also play both fullback spots. Walker Zimmerman is a center back. Moises Hernandez can play left back or center back (as can the last name on the list, Maynor Figueroa). Jesse Gonzalez is FCD's starting goalkeeper. Tesho Akindele can play up front or on either wing. Atiba Harris has mostly played right back in Dallas, but has a past playing as a winger, striker, and even defensive midfield.

In other words, the Hoops have had their back four thoroughly gutted by having to play right now. It's not just depth, either: We already mentioned Gonzalez as a starter, and he's joined by Zimmerman, Figueroa, and arguably Harris (who is in a battle for the right back job with Ryan Hollingshead). Given the glut of defensive midfielders on Oscar Pareja's roster, Acosta might have been a candidate to fill in for Figueroa. If Acosta wasn't used at left back, Hernandez would have been a likely choice instead.

It's gotten bad enough that, as Big D Soccer points out, Dallas may arrive at RFK with every single available player in their travel squad. On Filibuster this week, Ben Lyon (who also writes for BDS) mentioned the possibility of going to three at the back simply out of necessity. It's a bit of a throwback to MLS's first decade, where playing through the international window left teams traveling with short benches and playing unusual formations that never appeared again.

So with that in mind, here is how Dallas would line up if they stick with their normal 4231:

Gonzalez will be replaced by Chris Seitz, who despite being in his 10th MLS season has just 64 total league appearances. He's still a pretty solid back-up though, so United won't be getting that great of an advantage shooting at him. Still, it seems advisable for the Black-and-Red to repeat their recent tendency to fire away (though hopefully the shot locations start to improve a bit).

The back four, despite being bare bones, still features 3 players with regular starts in 2015. Matt Hedges is a top-tier MLS center back and will surely start. His partner from last season, Zach Loyd, missed most of the preseason due to injury and has yet to appear in an MLS match in 2016. However, he has been training at 100%, so he'll probably play left back. Loyd has played every defensive position for Dallas over the years, and the only other option to play there is Hollingshead, who seems more likely to start at right back instead.

Hollingshead is a pretty interesting case. Pareja has, in short order, converted a pretty unremarkable right winger into a marauding right back who is a legitimate threat as a creator and even to go to goal. His defending still isn't very good - particularly in terms of positioning and speed of thought - but his ability to attack often helps cover those weaknesses from being exposed. There's an interesting chess match at play here: Last week, United was heavily left-sided in possession, which could force Pareja to play him at left back and use the more conservative Loyd on the right. However, Patrick Nyarko's standout performance down the right wing would be a major problem for Hollingshead. This is a situation to pay close attention to at kickoff.

The final defensive option is Aaron Guillen, a Homegrown rookie with 0 pro appearances. He hasn't even made the Dallas gameday squad of 18 yet. However, FCD's choices are to give the kid a chance - and no coach in MLS is more likely to pick that option than Pareja - or to play someone with no center back experience alongside Hedges. Pareja has done that too, with Je-Vaughn Watson playing a couple games as a center back last year, but most likely we'll be seeing the athletic but raw Guillen make his pro debut.

All that's the good news for United. The bad news is that the midfield that makes FCD a contender is mostly intact. Acosta will probably be replaced by Victor Ulloa, who started 59 games across 2014 and 2015. He'll partner with Carlos Gruezo, a 20 year old with 2 appearances at a World Cup (for Ecuador) already on his resume. Gruezo came to Dallas from Stuttgart in the Bundesliga, in case you're wondering about his pedigree. Both players are very intelligent with and without the ball, and FCD relies on their smarts to slow teams down by taking their options away. However, both give away a lot in the size department - Ulloa is a thin 5'11", while Gruezo is 5'7" and under 150 lbs. - so United may have some success if they can force a physical game through the middle.

Ahead of them is one of the best attacking trios in MLS. Michael Barrios and Fabian Castillo have the speed to trouble any defense, and enganche Mauro Diaz is one of the best players in MLS. All three can break anyone down with their dribbling ability, but they're also comfortable combining in tight spaces when games aren't wide open. United is going to have to be very sharp as a group to minimize the times anyone in this trio can isolate a defender. There's a reason Castillo is talked about as a potential 8-figure transfer one day, and why your friends here at B&RU see Diaz as the ideal outcome for Luciano Acosta's development.

In particular, United needs to be aware of Castillo's ability to get into goalscoring positions. He's worked hard to add that to his game, and he's also become a better finisher over time as well. Sean Franklin had probably his best game of the season against Colorado, but this is going to require another step up from him (as well as Bobby Boswell and/or Kofi Opare, depending on how Ben Olsen aligns his center backs in Birnbaum's absence).

Up top, Maximiliano Urruti seems to have adjusted well to his move from Portland. The former Timbers supersub has 2 goals already, and his mobile, high-energy style seems to have been the right fit for playing with FCD's attacking trident. United has struggled with Urruti's darting runs and his sheer persistence in the past, and they're going to have to interrupt the bond he and Diaz have forged if they're going to come out on top Saturday.

Akindele's absence robs Pareja of his one way to change the nature of his attack. Without the physical, speedy Canadian, there's no proven game-changer available to change things up off the bench. However, German rookie Timo Pitter was their top scorer in preseason, which was an interesting development given that he was more of a playmaker in college. Former D.C. United under-23 striker Colin Bonner will also probably travel, and he'd offer the Hoops the ability to use a target man if they decide to go that route. It's worth noting that neither has made an FCD gameday squad yet, though.

One player who will almost certainly appear off the bench is Argentine veteran Mauro Rosales. Rosales ended up in Dallas after an odd trade in which Dallas and Vancouver swapped the MLS rights to Rosales and Blas Perez while both players were out of contract. The 35 year old Rosales doesn't have much in the way of speed, but he's a very smart and creative player whose ability to find his teammates (as a passer or with crosses) is a real threat. United will need to be in his face from the moment he comes into the game, be it on the right flank or to give Diaz a rest.

Another option, either as a forward or on the wing, is Homegrown product Coy Craft. Pareja recently said he was glad to have Craft back from meniscus surgery, but he's only been training at 100% for a week. I think he might travel despite that, and Pareja may still give him 10 minutes or so just to build some fitness and sharpness. We may also see an MLS debut for Colombian veteran Juan Esteban Ortiz, a defensive midfielder who has so far struggled to get past Gruezo, Acosta, and Ulloa in the rotation.

There's also the possibility that FCD goes to a 3412, in which case I'd expect a back three of Guillen, Hedges, and Loyd. Hollingshead would take over on the left wing, with Barrios on the right and Castillo moving up front as a second forward. It can't be ruled out given how short-handed Dallas is for this game, especially if United is holding a lead in the second half.