BEFORE LAST MONTH'S MEXICO friendly, I had not watched Julian Green play one minute of soccer. I hadn’t even seen Gedion Zelalem on a pitch. And unless you’re a fourth-division German soccer fan, Arsenal youth squad enthusiast, or a thoroughly obsessed U.S. supporter, there's an excellent chance you hadn’t either.

All of the reports sound promising for Green, including A) his scoring rate for Bayern Munich's U-23 squad (15 goals, 23 appearances); B) the fact that Pep Guardiola played Green (albeit in garbage time) during a Champions League match; and C) the German national team expressed enough interest to call Green to train with its U-19 squad.

So it certainly appears as though Jurgen Klinsmann pulled off a major coup in convincing Green to play his international soccer for the U.S. instead of Germany. While Zelalem hasn’t officially switched sides, he’s reportedly seeking U.S. citizenship, the first step in playing for the Stars and Stripes.

It also seems there’s some trepidation in crowning Green the Next Big American Thing given our nation's history of young studs fizzling, dissipating into the soccer ether. Just about every candidate to “save” U.S. soccer has disappointed in one aspect or another.

So why have they failed? How, with all the hype and infrastructure and opportunities, did few wunderkinds excel and most flame out, stoking fan’s dreams before having them harshly extinguished?

Here’s a partial list of would-be stars, attacking players one and all, who were forced to lift a heavy burden early in their careers—they were all labeled game-changing prospects with the potential to put American soccer on the international map. They are listed below in descending order of hype. We excluded players before the 2002 World Cup cycle, given the lack of academy infrastructure and training facilities/programs to cultivate talent.

Freddy Adu

Freddy Adu was Major League Soccer's poster child long before David Beckham considered life in Southern California, joining D.C. United at the age of 14, appearing 30 times, scoring five goals, and notching three assists. Against grown men. In his first season. At 14.

Adu chose going pro in America instead of enlisting in Inter Milan’s academy under his mother’s advisement. Adu was everywhere, from The Late Show with David Letterman to Total Request Live and even 60 Minutes. His Q-score was off the charts—far higher than any other American soccer player. He also performed well for the youth national teams, scoring tons for the U-17s and U-20s, including captaining the U-20 World Cup squad to the quarterfinals in 2007, which, in hindsight, was one of the federation’s youth best teams in history. Michael Bradley and Jozy Altidore also played on that side, but Adu led the way—feast upon the 6-1 demolition of Poland and the skill Adu displayed.

Post-D.C., Adu spent a season at Real Salt Lake before hopping to Portugal’s Benfica. What follows is an impressive record of not playing for five clubs in four countries over as many seasons. He played no more than 11 times at each stop, which included AS Monaco, Belenenses (Portugal), Aris (Greece) and Çaykur (Turkey). For his 90 some-odd minutes played in the 2011 Gold Cup, Adu sparked the sputtering U.S. attack, garnering hockey assists for the Clint Dempsey/Costa Rica goal in addition to the Landon Donovan/Mexico finish while also assisting on Michael Bradley’s header against El Tri.

But an MLS stint with the Philadelphia Union and Peter Nowak’s inexplicable dealings impeded any progress or vital signs shown that summer, his last appearance for the national team coinciding with Bob Bradley’s. The cord was cut, and Adu’s career flatlined.

His downfall? Hubris, possibly. Who knows where he could be now had he played with Inter’s U-18s or U-20s? (Granted, that one’s more on his mother, for not wanting to send her 12-year-old son overseas.) His defense is either atrocious or non-existent. In today’s game, that’s tactically implausible and inexcusable. He played just twice in Brazil’s Série A last season.

Maybe making $550,000 per year at age 14 made any lesser salary seem unpalatable; no team would copy Philadelphia and make Adu a designated player these days. He’s the poster child of unfulfilled hype, potential, and expectations. Is he one of the U.S.’s best 23 players? No way. But is he one of its best 23 talents? A case can be made, and that makes him one of U.S. soccer's greatest disappointments.
Bottom Line: A debilitating hit to the talent pool.

Landon Donovan

Donovan is the best-ever player to lace up his boots for the United States. His play is/was never sexy—he doesn’t have the dominant physical attributes of Cristiano Ronaldo or Lionel Messi’s deft skill. But as Brian Phillips wrote, he’s the mercurial, often-candid star the U.S. got.

Donovan latched onto Bayer Leverkusen early, signing at six-year deal at 17 before returning to MLS. In his prime, he could run past just about any defender who sized him up, finessing his way into an optimal scoring opportunity for either himself or a teammate. Accordingly, he holds national team records for goals and assists. He scored against Mexico at the 2002 World Cup and was honored as the tournament’s best young player.

But more was always wished for Donovan. He appeared seven times for Leverkusen but was ultimately sold to the Los Angeles Galaxy. His Bayern Munich loan spell in 2009 consisted of six appearances. The unconquered land of Europe would remain as is. Clint Dempsey and Michael Bradley flourished in two top-flight leagues before returning to MLS, but one can’t help but imagine the possibilities if Donovan had felt more comfortable plying his trade in England or Germany on an ongoing basis.
Bottom Line: Great success, but the “what ifs?” will linger

John O’Brien

In U.S. soccer’s modern era, O’Brien was the original savior. A product of the Ajax youth system, where he began training at 17, O’Brien lept to the senior side in 1999. He played a significant role in the Dutch giant’s Eredivisie-winning 2001-02 season. Of all non-keeper Americans abroad, O’Brien was the most prominent and productive American ahead of the 2002 World Cup. He was electric and calming in the middle, pairing beautifully with Claudio Reyna.

But injuries piled up on O'Brien, and never relented. From 1998 to 2006, between club and country, the Los Angeles native played about four seasons worth of games. He returned to the States and suited up for Chivas USA in 2006 but logged just one appearance, then decided to retire.

Unlike others on this list, O’Brien reached his potential, or something approaching it; it's just that his body could not sustain it. What hurts is that we may be seeing this play out to an extent with another American talent—Bolton midfielder Stuart Holden, who has suffered knee injury after knee injury after knee injury, unable to remain on the pitch.
Bottom Line: His star shined brightly but burned out fast.

Santino Quaranta

Many of these stories follow a similar path: early success derailed by injuries. It’s a “Mad Lib"—just fill in different names and jerseys and years. And to some extent Quaranta fits the bill: five goals and an assist in his first season with D.C. (what’s with United taking all these young kids?) in 2001, where he among others on this list led MLS’s “youth movement." Struggling through injuries, he rallied for the 2005 season, scoring five goals and tallying five assists in 18 appearances.

But Quaranta's tale veers off in a different, darker direction. In the middle of his short career, Quaranta turned to drugs, notably OxyContin and cocaine, telling The Washington Post, “There weren’t enough pills in the world for me. You could have put me in Iraq and I would have found a way to get pills. I should have been dead a long time ago.”

He tested positive in 2006 and sobered up the following year. Though he recovered and completed a few strong years in D.C., it was too late. By then he had thrown away a spot on the 2006 U.S. squad that fell flat in Germany, and his international career was over.
Bottom Line: The most tragic story of the bunch.

Jamar Beasley

Before DaMarcus, there was Jamar, the first of many high school phenoms to join MLS. Sports Illustrated called him soccer’s Kobe Bryant, more for shared circumstances than skill. But this Beasley had his first crack at American soccer, starting in New England. With quotes like, “He's got the technical ability of a Brazilian player, the speed of an American sprinter, and the mental speed and toughness of a Western European player” from then-coach Thomas Rongen, people were excited. After four, at best, mediocre, seasons in New England, he joined his much more successful brother in Chicago for a season.

After that? Poof. No more Jamar. He turned to indoor soccer and futsal to try to resuscitate his career—to no avail. In 2010, Sporting KC signed him and subsequently paid him $40,000 to… do nothing. Early in his career, he turned to excessive drinking and partying with some Boston Celtics, including Paul Pierce, and “stumbled into practice either hungover or maybe still slightly drunk, gradually eroding any confidence or patience a club could ever have in him,” leading to his Revs departure. This year you should be able catch Jamar in some Major Indoor Soccer League action while DaMarcus thrives in Mexico, expected to be on the United States' 2014 World Cup roster.
Bottom Line: A self-proclaimed cautionary tale of wasted talent.

Eddie Gaven

Eddie Gaven debuted with notoriety, as MetroStars manager Bob Bradley subbed Gaven in as a goalie substitute and New York’s fourth sub, promptly switching back with Tim Howard, a rule MLS would scrap shortly thereafter. In double-overtime, he flew down the left wing and put away the gamewinner. The next season, 2004, Gaven became the youngest player named to MLS’s Best XI. Wahl posed that he “could have the brightest future of any U.S. prospect” in 2006. Simply put, Gaven balled.

But it never fully came together. Nothing dramatic or scandalous. Gaven completed a nice career last October, acting as the Columbus Crew’s midfield stalwart from 2005 until his retirement following an injury-plagued season. He received the random national team call-up every now and then, but it never stuck.
Bottom Line: Nope.

Juan Agudelo

Adu's rise and subsequent fall should have tempered America's expectations. We should have been immune to the wunderkind hype. But then a 17-year-old Juan Agudelo had to go out less than a week before he could legally buy a pack cigarettes and score a dramatic winner against South Africa.

In his second match for the U.S. senior team, he nailed an equalizer against Argentina.

“What a story! You could not write this stuff,” commentator John Harkes exclaimed.

“Everyone wants to avoid an overhype situation a la Freddy Adu/Eddie Johnson, but in his first three U.S. games Agudelo is making it hard for U.S. fans not to get excited,” Grant Wahl wrote, then wondering, “At what point does he get his first U.S. start?” In the 16 appearances that followed, Agudelo failed to find the net.

He has been traded within MLS twice, transferred to Stoke City, and loaned out to the Eredivisie’s FC Utrecht. So he’s in demand. Plus, he's just 21. You know who was also having problems at 21? Current starting striker for the U.S. men’s national team: Josmer Volmy Altidore.
Bottom Line: There’s still hope.

Jozy Altidore

Speak of the devil! It wasn’t too long ago that Altidore was considered a bust after exploding on the scene for the New York Red Bulls. Just before a solid 2009 Confederations Cup, Altidore fetched the highest transfer fee for an American player (since tied by Michael Bradley to Roma), ponied up by Spain’s Villarreal. Again, Wahl wrote, “Poised, polished and just 19, Jozy Altidore looks set to reach heights unprecedented for an American.”

Then it got rough, as Altidore endured a difficult stretch with the Premier League’s Hull City, recording as many league goals as red cards (one). His national team form declined after the 2011 Gold Cup, during which he strained his hamstring.

Apparently all Jozy needed to do was play in the Eredivisie, where he torched defenses, leaving scorched defenders in his wake. Altidore thrived for AZ Alkmaar, tallying 31 goals in 41 total appearances. No one could stop him. After a 19-month scoring drought for the Stars and Stripes, he crushed three friendlies and four World Cup Qualifiers in the back half of 2013, scoring eight times. He was named U.S. Soccer's 2013 Male Athlete of the Year, and he seemed to be on the verge of reaching his tremendous potential.

And then Sunderland happened. Altidore joined the Premier League club at the start of ther 2013-14 season, and it hasn't gone well. Say what you will about the quality of his teammates and the lack of service received, but one goal all season is poor. At 24, maybe Altidore’s quality falls short of what’s needed in the Premier League. Though he’s still the United States' No. 1 striker, former club and current national teammate Aron Jóhannsson is making noise back at AZ.
Bottom Line: Re-evaluation required after the World Cup.

Guillermo “Memo” Gonzalez

Oh, Memo. What could have been. An IMG Academy classmate of Gaven and Adu, the Los Angeles Galaxy drafted 16-year-old Gonzalez eighth overall. He started in the 2003 U17 World Cup. Everything looked good, the right boxes of “likely to succeed” checked off. But nothing.

The top Google result for “Memo Gonzalez” these days is “Memo Gonzalez & the Bluescasters,” not the guy who made a dozen MLS appearances in four seasons. Perusing a precious primary source—BigSoccer forums—a poster known only as "TheCadaver" blamed Memo’s effort and soccer acumen. We're going to defer to him on this one.
Bottom Line: Nada.

Bobby Convey

Convey joined MLS as a teenager, debuting for D.C. United—there's that team again!—at 16, drafted as a Project 40 player (now known as Generation Adidas) after being in the inaugural class of the Bradenton Academy. Through three MLS seasons, Convey excelled, eventually drawing the eye of Tottenham. Unfortunately for Convey, he was denied a work permit and eventually landed at Reading in 2004. He performed well and helped the team earn promotion to the Premier League in 2005. He also started two games in the 2006 World Cup, placing the free kick that led to Italy’s own goal in the group match. Promise! Dreams coming true!

Not so much.

After the Cup, a training ground knee injury sidelined him, he fell out of favor with club and country, and he recorded his last cap in 2008. Also, it turns out, Convey isn’t one of soccer’s winning personalities. Playing for quality MLS coaches in Frank Yallop and Peter Vermes, Convey wasn’t long for either San Jose or Kansas City. His relationship with Bob Bradley has been called “chilly.”

Since his return to MLS in 2009, Convey’s current stint with the New York Red Bulls means the 29-year-old will have put on four different shirts in six seasons. Describing the trade that sent him to Toronto from KC, Steve Davis writes, “No matter how you describe the exchange (note: a first-round pick in the ’14 supplemental draft), it’s a pittance for what we all thought this guy would be worth. At age 29, Convey should be in the prime of his career, still young enough to do, but now old enough to know.”
Bottom Line: Cooler heads failed to prevail.

Luis Gil

Gil developed with Generation Adidas and chose to sign with MLS instead of going overseas. Real Salt Lake brought him along slowly, loaning him to AC St. Louis in 2010 and giving him his MLS debut a season later at the age of 17. By last season, he was a regular fist-choice player for one of the league’s model franchises.

Gil starred on the disappointing squad at 2013’s U20 World Cup but fired a howitzer in a 4-1 loss to Spain. Last February, Gil played his first game for the U.S. senior team, the January camp match against South Korea in his native Southern California. He likely won’t travel to Brazil, but Gil’s slow and steady development passes the smell test. He received less hype than others on this list, he wasn't asked to do too much too soon, and it's perhaps no coincidence that his prospects look good.
Bottom Line: His best is still ahead.

OF COURSE, Green and Zelalem probably won't be given a chance to develop slowly. Part of that comes with playing for Bayern Munich and Arsenal. Part of it comes from associating with the United States, a country that is still desperate to anoint its first international superstar.

Before the last World Cup, ESPN ranked the top 50 players to play in South Africa; Landon Donovan was the only American present, slotted at No. 50. That’s not what American fans crave. They want someone on Ronaldo’s level. They want Maradona donning the Stars and Stripes. A player of that caliber would legitimize U.S. soccer to the world and to itself. Even though the team is good, the stigma still exists. Is Green that good? It’s too early to tell, but probably not.

Former D.C. United keeper Mike Ammann was prescient in his evaluation of overhyped American youths, telling Wahl, “These kids are great for soccer, but it’s also a negative because we're putting undue pressure on them to come in so young and make a difference.”

The failed stars were built up and torn down, like clockwork, stuck in the all-consuming hype machine placing unprecedented expectations on teenagers during the infancy of U.S. soccer's modern era. There was a slim chance that American soccer fans' wildest dreams would become a reality for these budding talents. No matter what becomes of Green and Zelalem, hopefully that cycle ends—not for U.S.’s soccer’s sake, but for theirs.

Will Robinson is a writer based in Los Angeles. Follow him on Twitter.