The United States' World Cup campaign is over, meaning we're already diving deep into the time-honored tradition of looking ahead to the next World Cup. In many cases, this means projecting a dream 23-man team with a mixture of current stars and youth prospects, but we're not going to do that here, because that's silly. Go look up some 2014 roster projections written in 2010. I guarantee you will laugh so hard that it will bring you to tears.

Instead, we're going to take a different approach and list off the players you should be keeping an eye out for. They're organized into tiers; some are not even American yet, some will play national team soccer as soon as this fall and some will be on the outside looking in for life.

We'll start with the current 23-man World Cup squad, work our way down to total mystery players and close this out with fringe players who are not currently considered to be USMNT players, but could experience a career resurgence.

The future, right now!

These are players who are currently 23 or younger that did not play starting roles this time around. If they continue to get better and progress in their club careers, they could be the team's stars in 2018. Or they could fall off and work their way out of the national team picture entirely.

DeAndre Yedlin (Seattle Sounders) - A surprise inclusion on this World Cup team, Yedlin's stock has risen considerably after three very solid performances in Brazil. Of course, the issue that most have with Yedlin still exists: as amazing as he is going forward, he's a pretty lousy defender for a right back. He's only 20 and has only been a defender for three years, so he's probably going to get better, but you should prepare yourselves for four years of debates about whether Yedlin is a fullback or a winger.

John Brooks (Hertha BSC) - Brooks' club team Hertha Berlin stayed up in the Bundesliga and they're ready to spend a bit of money to ensure they stay there again. He'll probably enter the season as a starting central defender for them, and he's only going to get better as he gets more playing time in the Bundesliga.

Mikkel Diskerud (Rosenborg) - To the surprise of many, Diskerud and Timmy Chandler were the only outfield players that did not appear in the World Cup. It doesn't help that he's a bit of an attacking midfielder/central midfielder tweener, and that he's not that visible at Rosenborg. He could really use a transfer, provided that staying in Norway isn't a family-oriented decision for the Norwegian-American (it might be).

Aron Johannsson (AZ Alkmaar) - He got one opportunity -- after Jozy Altidore went down injured -- and did so little with it that Jurgen Klinsmann changed his formation for the rest of the tournament. That's not a great look. He scored a lot of goals in the Eredivisie, but that's less impressive than scoring lots of goals in MLS. He would probably be very well served by seeking employment in France or Germany.

Julian Green (Bayern Munich) - Beyond any shadow of a doubt, the best prospect the United States has ever had. But he's buried on the bench at Bayern Munich, playing in the 4th division for their reserve team. That's no good for him, so many Americans will be hoping he gets loaned out to a top 2. Bundesliga or lower-table top-division club, but Pep Guardiola reportedly thinks highly of him and think he's best served training with Bayern's senior team while making sporadic bench appearances.

Still in the picture

These guys will be 33 years old or younger by the time the next World Cup rolls around, meaning they'll remain in the picture to make the squad as long as they continue to play at a very high level. Because these guys are already established pros, they're just getting listed. We don't need to explain what's up with this group. It will be stunning if Brad Guzan is not the U.S. No. 1 for the next four years.

Brad Guzan (Aston Villa)

Omar Gonzalez (LA Galaxy)

Matt Besler (Sporting Kansas City)

Geoff Cameron (Stoke City)

Timothy Chandler (Eintracht Frankfurt)

Fabian Johnson (Borussia Mönchengladbach)

Michael Bradley (Toronto FC)

Alejandro Bedoya (Nantes)

Graham Zusi (Sporting Kansas City)

Jozy Altidore (Sunderland)

So long, and thanks for the memories

Here are the players who will be 35 or older by Russia 2018. They might stick around for Gold Cup, Copa America and maybe even some qualifiers, but it would be shocking to see any of this group make the team four years from now. We thank them for being the best.

Tim Howard (Everton)

Nick Rimando (Real Salt Lake)

DaMarcus Beasley (Puebla)

Jermaine Jones (Besiktas)

Brad Davis (Houston Dynamo)

Kyle Beckerman (Real Salt Lake)

Clint Dempsey (Seattle Sounders)

Chris Wondolowski (San Jose Earthquakes)

Not technically American yet

These players are arguably the biggest USMNT prospects out there at the moment. They are also not yet American citizens. The path to citizenship is not complex for any of them, but it takes a father's decision in one case and time for the others.

Gedion Zelalem (Arsenal) - The Arsenal prodigy currently plays youth soccer for Germany, but will gain American citizenship if his father -- who is eligible -- becomes a citizen. There were rumors floating around before the World Cup that his father will become a citizen and that Zelalem will choose to play for the United States, but there's no concrete evidence to suggest he'll be suiting up for the Stars and Stripes. He's been compared favorably to former Arsenal and current Chelsea midfielder Cesc Fabregas.

Diego Fagundez (New England Revolution) - Possibly the second-best American or potentially American prospect at the moment behind Zelalem. The New England Revolution attacker has his green card and should become a citizen in two years, if he continues to reside in the U.S. and pursue it. He's turned down call-ups to the Uruguay Under-20 team to keep his American eligibility intact, but that doesn't mean he won't eventually change his mind and choose the country of his birth.

Darlington Nagbe (Portland Timbers) - The Portland Timbers' star youngster is on the path to citizenship and should be eligible to play for the United States by 2016. Because his home country of Liberia isn't a threat to get out of African qualifying, Nagbe should end up playing for the USMNT. He's an extremely talented and versatile attacker who can play on the wing, as an attacking midfielder or as a second striker.

Kekuta Manneh (Vancouver Whitecaps) - Even though Manneh currently plays in Canada for the Vancouver Whitecaps, he was adopted by American parents and can reportedly become a citizen. He has been called up by Gambia before, though, and reportedly rejected his last call-up due to an injury, not because he didn't want to play for the team. Manneh's path to citizenship and desire to play for the USMNT is a minor mystery, but the 19-year-old attacker will become one of the best young American players once he actually becomes American.

In a weird state of eligibility

These players can play for the United States whenever they want to. Problem is, they're yet to show that they want to. We've seen them in the pro or Under-20 ranks, so they're not really mysteries. We'll get to the mystery players later.

Juan Pablo Ocegueda (UANL Tigres) - A Mexican-American left back currently bouncing around Liga MX youth teams. He played at the Under-20 World Cup opposite Yedlin in 2013, but said he would no longer play for the U.S. when he was loaned to Chivas Guadalajara, who has a Mexicans-only policy. However, his loan expired without Chivas purchasing him, so he's back at UANL Tigres, meaning there's no longer a club-country conflict for him.

Shawn Parker (Augsburg) - Parker is German-American and his father is a citizen, so he can play for the United States at any time. The 21-year-old striker has represented Germany at youth level and just moved to FC Augsburg, where he should get more playing time than he did at Mainz. He's publicly stated that he is open to playing for the United States.

Could play for the USMNT immediately

These are younger players who are already established professionals. In four of these five cases, they've already played senior national team games. It would be stunning if they did not get call-ups over the next year and plenty of chances to prove to Jurgen Klinsmann that they deserve to be part of the furniture.

Luis Gil (Real Salt Lake) - The young Real Salt Lake star has one cap at senior level and was the United States' best player at the Under-20 World Cup. He's only 20 and he's already one of the best players in MLS. Expect him to get looks from Klinsmann very shortly.

Wil Trapp (Columbus Crew) - Another standout from the last Under-20 World Cup, Trapp has made a massive leap this season. He was a bit part player for Columbus in 2013, but was one of their stars in the first half of the 2014 season. If this last World Cup marked the end of the road for Kyle Beckerman, Trapp's pretty close to a like-for-like replacement.

Terrence Boyd (RB Leipzig) - When Altidore went down injured, a lot of fans were upset that Boyd wasn't there to replace him. He's a true target forward who has been lighting up the Austrian league and just moved to RB Leipzig, an ambitious 2. Bundesliga club backed by Red Bull, who are spending money to get them into the top flight.

Juan Agudelo (Unattached) - After a surprisingly great comeback season with the New England Revolution, Agudelo signed for Stoke City. However, he was unable to get a work permit, so he was loaned to Dutch side FC Utrecht. He performed well in the Eredivisie, but still couldn't get a work permit, so Stoke have let him go from his contract. Where he goes next will be crucial for his USMNT future.

Brek Shea (Stoke City) - Assuming he actually gets to play somewhere, Klinsmann would really like to have Brek Shea at his disposal. He's the team's only true left-footed left winger, an incredible athlete, a great defensive winger and a fullback in a pinch. Basically, he's left-sided DeAndre Yedlin. Problem is, he's not playing a lot of competitive soccer. He needs a great loan or a transfer from Stoke, ASAP.

Prospects a year or two away

This is the biggest group of the bunch, so clearly some of these players will never reach their full potential and will stagnate over the next couple of seasons. One or two of them will probably become key starters for the USMNT by 2018.

Gyasi Zardes (LA Galaxy) - The 22-year-old attacker is a late bloomer, but one with enough talent that MLS gave him a pretty sizable contract to keep him from going to Europe. He looked outrageously raw for someone his age last season, but he's started to look like a very solid starter for the LA Galaxy in 2014. His combination of size and pace is terrifying.

Shane O'Neill (Colorado Rapids) - O'Neill has become a key player for the Colorado Rapids at just 20, but the one thing that could hold him back at the national team level is that it's not clear what his best position is, or if Klinsmann, Under-20 coach Tab Ramos and the Rapids all agree about that. He's adept at central defense and defensive midfield, though he's played more center back. There's one complication with O'Neill, though: he's also eligible to represent Ireland.

Kellyn Acosta (FC Dallas) - Very similar to Yedlin in that he's an extremely raw, athletic fullback who doesn't actually know how to defend yet. But Acosta is just 18, he's already getting Under-20 national team time and he's a competent MLS starter. It wouldn't be shocking to see him improve to national team level by late 2015.

Paul Arriola (Tijuana) - Arriola is one of a handful of Mexican-Americans who play for Tijuana, and he might be the most talented of the bunch. The 19-year-old has scored goals in Liga MX and CONCACAF Champions League, though it's not clear how much playing time he's going to get at Tijuana going forward.

Will Packwood (Birmingham City) - After a strong second-half season performance in the Championship for Birmingham City, Packwood is being billed by some as a breakout player for the United States in late 2014 and early 2015. The 21-year-old is an athletic 6'3" central defender and will certainly start to get some looks if he's starting every game for Birmingham.

Joe Gyau (Borussia Dortmund) - Gyau has been on USMNT fans' radars for a while, and we're getting dangerously close to forgetting about him as an immediate USMNT player. But the athletically gifted winger is still just 21, and has plenty of time to get better. However, he's made the curious decision to sign for Borussia Dortmund, who will almost certainly give him no chance to play first-team soccer. He'll be playing for their B team in the 3rd division of German soccer this season.

Zach Pfeffer (Philadelphia Union) - It's tough to know what to make of Pfeffer. He was billed as the star midfielder of the future when he made his first team debut for the Philadelphia Union in 2011, but three years later, he looks no closer to becoming an established pro. The good news is that he has looked excellent in recent Under-20 national team performances, so a step up might be coming soon, but the Union have a pretty bad track record with mismanaging their prospects.

Bobby Wood (1860 Munich) - Wood has one senior cap to his name, picked up last August, but he's stagnated since then. Klinsmann and the coaching staff at 1860 Munich were gushing about him going into last season after a strong finish to the 2012-13 campaign, but he failed to meet expectations. He's just 21, so that breakout season could be coming, but like Gyau, he's only a year or two from being forgotten about if he doesn't pick it up.

Dillon Serna (Colorado Rapids) - Serna was a huge star in college and for the Under-20 national team, but he stagnated a bit last year, missing out on the Under-20 World Cup and failing to play much for a Colorado Rapids team that isn't shy about throwing youngsters into the fire. Serna's getting a bit more playing time this season, though, and could break through as a star in MLS come the 2015 season.

Marco Delgado (Chivas USA) - Because he plays for perpetual MLS laughing stock Chivas USA, Delgado has seriously flown under the radar, but the 19-year-old has established himself as a solid MLS starter this year. He looks like he's on the Luis Gil Path To Success™, going from barely playing at 17, getting time at 18 and establishing himself in the first team at 19. The last step is to become a starting XI lock and borderline all-star at 20.

Jack McBean (LA Galaxy) - When McBean signed for the LA Galaxy at 16 and looked like a competent pro in some limited substitute appearances, most assumed he was on his way to becoming a star. Three years later, McBean is 19 and not yet a first-team player for the Galaxy. However, he hasn't been awful in his limited opportunities and has all of the physical tools to make the leap shortly.

The big-time teenagers

We haven't seen enough of any of these players to know if they'll even be solid professionals, but they're the youngsters with limitless ceilings. There might be a Clint Dempsey or Landon Donovan in this group, and there might be no future national teamers at all. It would be surprising if more than one of these players was genuinely national team ready by 2018, but you never know.

Joshua Perez (Fiorentina) - The former crowned jewel of the Chivas USA academy is just 16, so you'll have to wait a while to see him, but he's considered the biggest prospect in the country at his age group. He's already training with Fiorentina in Italy after leaving Chivas.

Junior Flores (Borussia Dortmund) - Flores is a couple of years older than Perez and also the biggest prospect in his age group. He's agreed to sign for Borussia Dortmund, where he'll get some time alongside Gyau in their reserve team this season, and he should be one of the stars of the United States' 2015 Under-20 World Cup team if they qualify for the tournament.

Jordan Morris (Stanford/Seattle U-23) - If you live in the greater Seattle or Palo Alto area, why not take the opportunity to go see Morris yourself? He's playing this spring season for Seattle Sounders Under-23s in the USL PDL, then will probably play one more season at Stanford before turning pro and signing with Seattle. He's the biggest USMNT prospect currently attending college.

Erik Palmer-Brown (Sporting Kansas City) - This 17-year-old Sporting Kansas City product has looked pretty raw in his limited pro appearances, but that's to be expected from a central defender of that age. He has so much upside that Juventus made a seven-figure offer for him, but Sporting KC turned them down.

Joe Gallardo (Monterrey) - If we're lucky, we'll get to catch Gallardo making some appearances for Monterrey in mop-up duty and non-league competitions this season, but he's probably still one year away from that. The 16-year-old forward has been lighting it up for the U.S. Under-17s, but it's anyone's guess if or when he'll be ready to make a jump up. He's regarded as a massive prospect, but that doesn't mean we'll get to see for ourselves anytime soon.

Emerson Hyndman (Fulham) - Hyndman is the grandson of former FC Dallas manager and college coaching legend Schellas Hyndman and plays in midfield for Fulham's youth team. He was a regular in the Under-18s during their run to the FA Youth Cup final and could end up playing a regular role for their Under-21 squad this season.

Zack Steffen (Maryland) - With Cody Cropper -- who we'll get to -- turning 20, Steffen will probably become the starting Under-20 keeper shortly. He was spectacular in his freshman season at Maryland and will almost certainly have offers from pro teams in Europe before he finishes college. He's also eligible to sign for the Philadelphia Union as a homegrown player, but since they have Andre Blake and Zac MacMath on their books, you'll likely see him pop up elsewhere as a pro in a year or two.

Wait, where's that Barcelona kid I've heard of?

Ben Lederman (Barcelona) - He turned 14 in May. Barcelona can't find a place in their first team for Rafinha Alcantara. Please stop.

The solid pros

These players are established as professionals and will almost certainly get Camp Cupcake or off-year Gold Cup shots at some point in their careers, but they may have reached their ceiling. No one is expecting these guys to become stars, but there's probably a Graham Zusi or Matt Besler lingering in this group.

Harry Shipp (Chicago Fire) - Having a great rookie season for Chicago, but already 22 and not a superstar physically.

Josh Gatt (Molde) - Numerous injuries and failure to move anywhere bigger than Molde probably mean Gatt will never reach his full potential.

Amobi Okugo (Philadelphia Union) - An excellent MLS player, but he's short for a defender and technically limited for a midfielder.

Jack McInerney (Montreal Impact) - Still 21, so can improve, but his national team prospects have dwindled after a bad second half of the 2013 season. Stuck on a bad Montreal team, but scoring pretty regularly.

Andrew Farrell (New England Revolution) - He's not Klinsmann's kind of fullback, but he's a very good defender for a 22-year-old, 2nd year player. Kind of a throwback to the Gary Neville era of fullbacks.

Bill Hamid (D.C. United) - It seems harsh to relegate a 23-year-old goalkeeper to this category, but Hamid has been getting pro playing time since 2010 and isn't that much better than he was at 19.

Sean Johnson (Chicago Fire) - Will make the greatest save you've ever seen and the worst mistake you've ever seen in the same game about six times this season.

Perry Kitchen (D.C. United) - Extremely intelligent defensive midfielder and versatile player who has played central defense and right back competently, but a bit slow and average technically. Could become Geoff Cameron Pt. 2.

Dillon Powers (Colorado Rapids) - A member of the Graham Zusi All-Stars™. Spent a lot of time in college, was expected to just be a solid pro, but he's become a prime Camp Cupcake candidate for this January. Surprisingly good technically and balanced for an attack-minded midfielder.

Benji Joya (Chicago Fire) - A classic box-to-boxer who does everything well and nothing exceptionally.

Jose Villarreal (Cruz Azul) - Wasting away in Cruz Azul's reserves after some good MLS and Under-20 performances. Has a limited ceiling and, while he's a technically solid attacker, no true position.

Will Bruin (Houston Dynamo) - Brian Ching Pt. 2, and the fact that he plays for Houston is, like the Powers-Zusi comparison, a total coincidence.

Greg Garza (Tijuana) - Has shown some flashes of ability with Tijuana, but isn't getting tons of playing time and is now 22. He'll move to a smaller Mexican team or MLS team, become a good player and be a decent left back option in a pinch.

Eric Miller (Montreal Impact) - As always, a rock solid young MLS fullback will get a place on this list, since the United States always has shaky fullbacks. He'll be 33, you'll look at his Wikipedia page and go "whoa, Eric Miller has 10 USMNT caps?!?"

The mysteries

We admit to not having seen these guys play too much, but they're eligible for the United States and considered to be pretty decent prospects. Hopefully we get to watch more of them in the future.

Duane Holmes (Huddersfield) - A 19-year-old English-American who plays for Huddersfield in the Championship. He has said in the past that he sees himself as American.

Rubio Rubin (Utrecht) - A big prospect trying to make it at Utrecht in the Netherlands. He should be a starter for the Under-20s during their World Cup cycle; Tab Ramos reportedly likes him a lot.

Tyler Turner (Orlando City) - If we're lucky, we'll get to see a lot of Turner in 2015. The 18-year-old defender is playing a lot for third-division Orlando City SC, who will join MLS next season.

Cody Cropper (Southampton) - He was the Under-20 goalkeeper for a while and he's currently at Southampton in England. Cropper's too old to play for the Baby Yanks now, and he won't be starting at Southampton anytime soon. Goalkeepers should never be written off until they're 26 or so, but Cropper was shaky at Under-20 level and he doesn't seem to be close to getting a shot with a team that loves to throw teenagers into the first team.

Caleb Stanko (Freiburg) - Started at the Under-20 World Cup, currently in Germany. Hopefully he gets some time with Freiburg this season.

Mario Rodriguez (Borussia Mönchengladbach) - Like Stanko, it's tough to keep track of him playing in German reserve soccer (for a team that's not Bayern or BVB). He's currently at Borussia Mönchengladbach.

Alonso Hernandez (Monterrey) - Like Joe Gallardo, at Monterrey, and probably closer to first team soccer. He's played for the Rayados, but he's already 20 and time's running out for him as a "prospect". He needs to play real pro soccer, soon.

Marc Pelosi (Liverpool) - Was considered one of Liverpool's top prospects for a while, but suffered a serious injury that took him out of action for 14 months. He's played left back and left wing, and will get back on the national team radar if he's starting for Liverpool Under-21s and looking as good as he was pre-injury.

Omar Salgado (Vancouver Whitecaps) - Once the No. 1 overall pick in the MLS SuperDraft and a sure bet to be the next Brian McBride, Salgado has done almost nothing while with the Vancouver Whitecaps. The good news is that he's just 20, and that he did well during a recent loan to the Charleston Battery. It's too early to write Salgado off completely, but it's also impossible to tell what he's going to be.

Joel Sonora (Boca Juniors) - He was raised in Argentina, but burn in America, and Ramos has called him up to the Under-20s. Seems enthusiastic about playing for America, not trying to play for Argentina. But he's still just 17, so we might not see him for a couple years.

The fringe

These are senior players who have been called up by the USMNT in the recent past and are still young enough that they could turn their careers around. One or two players in this group will have a bizarre late-career resurgence and find themselves in the national team going forward, ala DaMarcus Beasley.

Mike Magee (Chicago Fire)

Eddie Johnson (D.C. United)

Tim Ream (Bolton Wanderers)

Chris Klute (Colorado Rapids)

Chance Myers (Sporting Kansas City)

Michael Parkhurst (Columbus Crew)

Edgar Castillo (Atlas)

Michael Orozco (Jaguares)

Tony Beltran (Real Salt Lake)

Alfredo Morales (Ingolstadt)

Eric Lichaj (Nottingham Forest)

Stuart Holden (Bolton Wanderers)

Jose Torres (UANL Tigres)

Joe Corona (Tijuana)

Maurice Edu (Philadelphia Union)

Danny Williams (Reading)

Benny Feilhaber (Sporting Kansas City)

Sacha Kljestan (Anderlecht)

Dax McCarty (New York Red Bulls)

This post is updated regularly. Check out Top Drawer Soccer and Yanks Abroad, which were invaluable resources in compiling this piece.