Editor's Note: Originally drafted by FC Dallas in the first round of the 2011 SuperDraft, Bobby Warshaw spent more than two years in Major League Soccer before he was loaned to Swedish club Ängelholms FF in August 2013. He joined Swedish club GAIS on a one-year contract in February. A former academic standout at Stanford University, he has also written for Deadspin.com and PennLive.com. His viewpoints do not necessarily represent that of the editorial staff of MLSsoccer.com.

I barely passed biology in high school, but I’m about to drop some science knowledge on you anyway.

Everything in the body is connected. The sore toe can lead to an aching shoulder. A tight hamstring rarely means that you actually have something wrong with your hamstring. One weak body part causes the next one to strain, and the dominoes begin to fall.

There’s one center, though. One anchor that can hold it all together. It helps relieve the stress on the body. It takes the bulk of the work and can absorb more abuse. It is the core. Those guys in 300 wouldn’t be nearly as scary if they didn’t have 6-packs that popped out of the screen.

The other body parts are certainly important: The arms lift the weight, the hands make the art, the legs do the traveling. They deserve their moment. But all are powerless without the spine.

The same is true for a team.

Some players are paid to score goals. Others are signed to make tackles or block shots. The arms, the hands and the legs. They need a core to hold them together.

On an MLS team, that core is typically made up of American players. Here’s the thing that we need to remind ourselves this time of the year: American players are the key to success in MLS.

Real Salt Lake's Kyle Beckerman (left) and Sporting Kansas City defender Matt Besler (right) are two of the American players in who "American players are the key to success in MLS." (USA Today Sports)

So a little R-E-S-P-E-C-T please.

Right now we are in Post-World Cup Silly Season, the summer months when gossip erupts about expensive players signing with new clubs. Every MLS club is linked with a big international. The fans write on Facebook that their club needs to splash the cash. And somewhere a fluttering butterfly dies.

Frank Lampard to NYCFC. Kaká to Orlando City. That’s all well and good. They are superstars who obviously raise the level -- and the profile -- of their clubs. Just don’t be surprised when the Budweiser Golden Boot goes to a dude from Chico State or the MVP goes to the guy sitting next to Robbie Keane at the Lakers game.

Here’s what we know about MLS: The season is grueling. There are games played in 100-degree heat after nine-hour travel days. Some nights you put in seven miles on concrete turf fields. It’s not a day in the park of playing the beautiful game. It’s a grind.

For all of the unique components that go into MLS – geography, weather, money – there is a certain style required to win. Maybe at some point the budgets will increase, the salary cap will go up and the game will evolve. But until then, bear down and buckle up.

You better have guys on the team that are ready to go 12 rounds. Pure talent doesn’t get it done. You need players that are willing to put in a good shift every single day. On any team in any league on any day, a player wants to be able to look next to him and know that his teammate will bust his ass for him.

Not coincidentally, that sounds a lot like what we saw from our guys in Brazil. We waved red-white-and-blue flags and proclaimed our national pride for the US team. We put our hearts on our sleeves, our throats in our stomachs, and not necessarily because of what the team inspired in our souls.

We cheered because they fought like warriors. Gritty, determined, hungry. The American Way, right?

There is a similar blueprint to success in MLS, and it largely revolves around the qualities that American players offer.

We have seen enough MLS teams try to play the beautiful game and fall flat on their face. You simply can’t put aesthetics over desire in MLS. You can play an attractive, skillful style – Real Salt Lake and the LA Galaxy have balled at times in recent years and been all the better for it – but they aren’t mutually exclusive. Skill can’t come without industry.

LA Galaxy defenders Omar Gonzalez (right) and AJ DeLaGarza were key cogs to the team's back-to-back MLS Cups in 2011 and 2012. (USA Today Sports)

At the heart of RSL's success in recent years has been Nick Rimando, Nat Borchers, Kyle Beckerman, Ned Grabavoy, Chris Shuler. The Galaxy had Omar Gonzalez, AJ DeLaGarza, Landon Donovan, Mike Magee and Todd Dunivant.

Colorado in 2010 had Matt Pickens, Drew Moor, Marvell Wynne, Jeff Larentowicz and Pablo Mastroeni. Kansas City last year had Matt Besler, Graham Zusi, Jacob Peterson, Chance Myers and Seth Sinovic. All of these teams have had big stars that stole the headlines, but their foundations were the hard-working Americans. It's important to build these players up and give them the credit they deserve.

I get the dilemma at hand. We want the best players on the field. International players often have more raw talent. The World Cup taught us that lesson, if we didn’t know it already. If one winger can do step-overs and curl a finish far post, he should play ahead of the other, less-talented option. Perhaps we truly aren’t producing Americans skillful enough to break open games yet.

Rarely, though, will internationals new to the league be ready for the MLS style right away. They might have the skill, but do they have the stamina and focus? It’s always fun seeing new, often well-respected international players whip their head in shell shock on their first day of MLS training. Their eyes have the “this stuff is going a million miles an hour” look, and they need to be pushed in the right direction. They need to be challenged and tutored in training. It takes a group of American players to set the tone for a team.

New York's Tim Cahill (left) and Thierry Henry are two big-name international players who have acclimated to MLS over previous seasons and succeeded. (USA Today Sports)

As I’ve talked this piece over with people, they’ve pointed out the international players that have been crucial to successful teams. They want Jimmy Nielsen, Jamison Olave, Paulo Nagamura, Alvaro Saborio, Donovan Ricketts and Juninho to get their credit. It raises the question that perhaps it’s not nationality that is the key variable, but instead time spent in MLS.

They might have a point. Players can get acclimated to the league. They can adopt American traits. Become Americanized, if you will. Some, very few, enter the league perfectly ready. Oscar Pareja and Peter Nowak certainly emboded the MLS spirit as much as anyone. Others simply start to care about MLS more over time – let’s call it "the Beckham Development."

International players have certainly been vital to MLS's success. I do not mean to take anything away from them. But we are talking about the core, the engine of a team that keeps it ticking, for which there is no substitute to born-and-bred Yanks.

As American fans, we still feel self-conscious about ourselves as a soccer nation. We feel the need for an exciting injection of foreign talent into our borders. We have the sentiment that if MLS wants to grow, it needs to do so from the outside in. I don’t know, maybe that’s true. I wouldn’t bet my house against it. But there’s a small flaw in the theory: As all these teams keep trying to improve from abroad, the teams built from within continue to win championships.

I’m not saying we shouldn’t get excited about new big names entering the league. It’s always good to raise the talent pool. But let’s not forget about the guys that make an MLS team tick. We might prefer to tweet about fancy goals from star players, but Americans are the heart and soul for MLS success.

I didn’t learn much in biology class. But I remember the heart and soul being pretty important. Take that, Ms. Shirey and your damned red pen. I paid attention sometimes.