Having talked about who might or might not make the USA Rugby World Cup squad among the forwards, we now turn our attention to the backs.

It's a sad fact that we will see fewer backs than forwards in the squad. That's partly due to the math—a rugby team carries 46.7% backs and 53.3% forwards. But using that math we'd end up with a forward-back split of 16-15 or 17-14. Instead, we're looking at 18-13, or even 19-12. 

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And that's because the game is so demanding physically on everyone, but especially the forwards, and more especially the front row, that you have to have some backup. And it's a lot easier to find a player who can play center, wing, and fullback (and maybe a little flyhalf) than it is to find a player who can play prop, hooker, and lock.

Anyway, 13 backs it is. We will need two or three who can play scrumhalf, two or three who can play flyhalf, probably four centers, three or four wings, and two fullbacks. Yeah, yeah, that's as many as 16 players, which is why we need players with some versatility.

Scrumhalf

How Many Needed: Two or three

Locked In: Shaun Davies, Ruben de Haas

On The Bubble: Nate Augspurger

Veteran Class: Mike Petri

Wow, this is a pretty impressive group. It's hard to imagine that Davies and de Haas have failed to do enough to make the team. All they have to do is keep doing what they've been doing and say healthy. 

Augspurger's status on the bubble is basically due to health. He was slated to captain the USA against the Maori All Blacks and then was felled by injury. He is flexible, however, and that helps him a lot. He plays wing, and does it well, so he has the inside track.

You know we like Petri. He's possibly the greatest American scrumhalf of the professional era. No one works harder or has a more professional approach. But he's not a long-term pick, and so is in the mix for all of those qualities, yes, but also in case something else happens.

So if Augspurger is good to go, we'll likely see three.

Flyhalf

How Many Needed: Two or three 

Locked In: AJ MacGinty

Logical Backup: Will Magie

The Future: Ben Cima

The Intriguing Option: Madison Hughes

There's no doubt that AJ MacGinty is the USA's most valuable back and it's unlikely that he will get much rest in the Rugby World Cup. But this summer? Yes, maybe. Gary Gold has to audition players, but the issue for us is that everyone is so different. 

For a player who has the ball in his hands a huge proportion of the time (assuming the Eagles can keep possession), the flyhalf's way of playing is very important, don't you think? We do.

MacGinty is a running flyhalf who tackles very well, has a solid pass, and is a superb goalkicker. His kicking from the hand is excellent, too, but he doesn't think kick first.

Magie kicks from the hand more, and isn't a blow-you-away runner. That's OK—he just needs to use his centers and support forwards more to make that initial line break. We'd like better defense from him, but his vision and his positioning at fullback are really strong.

Cima is an outstanding goalkicker. He's pretty clutch, too. He can tackle, and he elusive if not very quick. But has he put it all together? That's the big question.

Hughes can pass and kick and tackle, and we know he can run. But running a 15-a-side offense, which he hasn't done a lot of since college (and, really, that wasn't the same at all), is very different from how one operates in sevens. He knows this, but that doesn't mean the adjustment is easy.

Hughes could actually be a more MacGinty-like understudy to AJ, but then you'd likely need someone else to kick goals. Cima can play fullback. It is very difficult to pick. All three will be auditioning.

Center

How Many Needed: Three or four

Locked In: Bryce Campbell, Paul Lasike

Something To Prove: Martin Iosefo, Thretton Palamo

Crossovers: Ryan Matyas, Marcel Brache

We made crossovers a position in the forwards whereas here we just stick them in with the centers. Gold went through the ARC with Campbell and Lasike and that was it. Brache is definitely an option in the #13 jersey, and we'd be shocked if he didn't make the RWC roster.

So that kind of leaves one spot open. If it's Matyas, then you might leave a place open for one of the other two. It's hard to imagine both Iosefo and Palamo making the team. We haven't seen much of Palamo in an Eagle jersey. Remember, he made his debut 12 (!) years ago when he was a teenager. Now an old man of 30 (he will turn 31 just as the World Cup starts), Palamo still has a unique combination of power and elusiveness.

Of course, Iosefo has been in the arena, and is a devastating runner. He has the ability to transfer his skills to the more crowded 15-a-side field.

Wing

How Many Needed: Two to four

Locked In: Mike Te'o

Guys We Already Mentioned Who Are Likely: Marcel Brache, Nate Augspurger, Ryan Matyas

On the Bubble: Gannon Moore, Tim Maupin

We're listing Blaine Scully as a fullback, but of course he's also a wing. Versatility for a wing is key, and the guys on the bubble are really only wings who could play outside center at a stretch. Everyone else can play several positions. Te'o can play, like, nine (we exaggerate, slightly). 

The World Cup is a brutal test of a player's well-being, and you can't be caught short-handed. You need a wing who can battle it out in the midfield, and you need centers who are quick enough to cover on the wing.

All of these guys are good. This summer, Moore, Maupin, and maybe Matyas, have to blow some people away.

Fullback

How Many Needed: Two

Locked In: Will Hooley, Blaine Scully

On the Bubble: There is no bubble. This is it.

Hooley is pretty smooth under the high ball, can kick well from hand, and he's a solid goalkicker, too. Scully is faster, and often plays on the wing as a result, and bigger and probably a slightly better open-field tackler. 

It's a good combination because you have both of those guys back there you're in good shape to cover problems.

The Upshot

You could probably be pretty close guessing a starting lineup right now, but there are two or three spots up for grabs. There's also a chance that a player who has been capped repeatedly over the last few years gets left back home,

With the center pairing of Campbell and Lasike being kind of centers-only, versatility is very important for everyone else. Wings who can play fullback or center or scrumhalf have a far, far better chance of getting to Japan than those who can't.