Three years ago the American Outlaws put together a travel package in preparation for the 2014 World Cup in Brazil that included a charter flight from Houston to Natal and back, a 12-night hotel stay in Natal, gameday transportation, a charter flight to/from Manaus and a bus trip to Recife.

The founders of the U.S. soccer supporter group figured they'd be able to fill a plane by the time the global soccer tournament rolled around. What they actually got was an overwhelming flood of interest – so much so that they had to book another charter flight to accommodate the 540 people eager to root on the Americans in Brazil.

"We didn't really expect to get it this big," said Justin Brunken, co-founder and vice president of the American Outlaws.

And that pretty well sums up the exponential and unexpected growth of the Outlaws. Planning the trip to Brazil got so hectic that the American Outlaws hired travel agents to help with logistics.

"We thought it was going to take awhile to fill one plane and that was back in the day when one plane was actually less than what we have now. One plane was like 172 or something like that, now each plane is 200 and some. That's what we thought we were going to be able to do. We filled that one plane in less than 24 hours. At that point, we knew there was a lot of demand, a lot of people wanting to go with us. So, we started opening it up and we thought that 500 was probably still doable. We even had more people wanting to get in on our package and we had to cut it off at that point because that was the number that we thought could be manageable."

They were communicating with various people in Brazil and even brought on sponsors such as Degree, which will sponsor a daily video blog chronicling the group's travels, and Continental Tire, which will sponsor a pickup soccer game with Natal's club team, Club Americas de Natal. But even with the help there were perils of organizing travel for that many people. One of the flights had a time change, affecting the incoming travel of more than 200 people. Members of The American Outlaws executive board were forced to all fly in on Friday and fill in open seats on the Friday flight so that those who couldn't make Friday would still have a seat on Saturday.

View photos U.S. fans cheer on the Americans during a 2-1 friendly win over Nigeria on June 7. (Getty) More

It was the only time when the founders, Brunken and the president of the group, Korey Donahoo, started to question whether The American Outlaws had gotten too big for them to control.

"The thing that has been overwhelming, especially for Korey and Justin, who do more than any of us, for this travel package that we have, we have about 500 people going down to Brazil and those 500 people are relying on us to keep stuff under control and organized. We're chartering flights, which we've never done before," said Chris Donahoo, brother of founder Korey and event coordinator for the American Outlaws.

"They're getting stretched to where they're not sleeping and they're not eating well and it's taking a toll on their personal lives. Up until this point, that really hasn't been the case. And so I think that after the World Cup we can all take a deep breath and realize this thing has gotten a lot bigger than we thought it would be and we probably need to re-evaluate what we're going to do and how we're going to go about things going forward because it's just been too much."

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