THE 2013-14 EUROPEAN SEASON brought us the professional debuts of U.S. internationals Julian Green, Duane Holmes, Sebastien Lletget, and Sebastien Ibeagha. The season before that featured debuts of John Brooks, Will Packwood, Joe Gyau, and Terrence Boyd.

It’s hard to predict when a player is going to take the next step for a European club because so many factors are at play, but here is a list of some key Americans could make their professional debuts in the coming season.

Rubio Rubin

Rubio Rubin is perhaps the best teenage American prospect right now, and his decision to sign with Utrecht is looking better and better. There he will learn the game in a league full of good coaches and at a level where he can see first-team minutes at a very young age. Also, the Eredivisie is an offensive-oriented league—perfect place for a young forward like Rubin.

Utrecht rate Rubin very highly and see him as a player who can contribute as a teenager. The club also considers the 18-year-old Oregon native a player it can sell for a handsome profit in a few years.

Last season the U.S. U-20 striker trained at the club but was unable to play in official games because he had not yet turned 18. Last week he was injured in a collision in a first-team friendly and had to undergo surgery to reset his nose. Fortunately he shouldn’t be out of action very long.

As for this season, his first-team debut appears very likely and it shouldn’t surprise anyone if he does well.

Caleb Stanko

Caleb Stanko joined SC Freiburg in 2011 and has risen steadily through the ranks since that time. Last year he appeared to be closing in on his first-team debut when he was named to the matchday 18 twice (including one during the Europa League). While he was an unused substitute on both of these occasions, Stanko was rewarded with a multiyear professional contract in May.

So far this preseason the 20-year-old Michigander has been earning regular first-team minutes for Freiburg. Preseason minutes can be misleading, but the consistency with which Stanko has progressed tends to indicate that he is in the team’s plans.

It has been a while since an American-born-and-raised player has made it in the Bundesliga, and Stanko, the potential 2016 U.S. Olympic captain, seems on his way to doing just that.

Emerson Hyndman

Although it was relegated out of the Premier League last year, Fulham's future still looks bright because its youth teams are loaded with talent. Last year the club’s U-21 team finished in 5th place and went to the finals of the FA Youth Cup.

Emerson Hyndman has been a key part of the London club’s youth teams and the Texan has signed several contract extensions in recent years. So far this preseason he has earned first-team minutes and was recently named to Fulham’s short first-team roster that will travel to the United States to take on D.C. United this weekend.

It is still going to be tough for Hyndman to earn minutes this year as Fulham want to make a quick return to the Premier League but the signs remain positive for the highly rated 18-year-old.

Americans have a long history of success with Fulham: Marcus Hahnemann, Eddie Lewis, Carlos Bocanegra, Kasey Keller, Eddie Johnson, Clint Dempsey, and Craven Cottage legend Brian McBride all saw action with the club over the past 15 years. American fans would no doubt welcome another Yank in the mix at Fulham, and that could happen soon with Hyndman.

Devante Parker

Devante Parker and his older brother Shawn are the latest products in the impressive German-American pipeline. Yes, both Parker brothers are playing for German youth national teams at the moment, but Jurgen Klinsmann is well aware of both players and Shawn has even revealed that he has spoken with the American coach.

Shawn Parker, 21, has been in the Bundesliga for two years now and left Mainz last season for Augsburg. While he is doing well in preseason, Shawn Parker’s future with German teams looks limited and a switch could happen soon. The younger Devante Parker, however, looks like he could be a bigger catch if Klinsmann can swing it. Devante Parker, 18, was showing very well in preseason before an ankle injury slowed him down.

Still, the teenage Parker looks like a very safe bet to play for Mainz this season—which may lead to more dual-national tug-of-war stories.

Nicholas Gaitan

Last year Nicholas Gaitan joined Greek Super League club OFI Crete and played exclusively with the club’s youth team. This year, the Long Island native moved up to join the first team for the preseason and a permanent move to the senior squad appears to be within his grasp.

What is particularly interesting about this that OFI are now coached by former Italian national team star Gennaro Gattuso, and Gaitan plays the same position as the Italian legend. Gaitan, 19, hasn’t been able to get a sniff of the U.S. U-20 team this cycle, in part because his position is crowded with good players. Making some appearances for a good OFI team could only help make his case to Tab Ramos.

Others in the mix

Lynden Gooch has risen through Sunderland’s youth system for many years and has been playing well in first-team friendlies. Sunderland remains in the Premier League but another relegation battle might be forthcoming—not the ideal scenario for an 18-year-old looking to break into the senior team. Gooch made his Sunderland U-21 debut toward the end of last season, but if he continues to play and train well, domestic Cup appearances are a distinct possibility.

Similarly, Cody Cropper has also at times been knocking on the door of making his Southampton debut and has made the bench on occasion. The 21-year-old is still very young for a goalkeeper but if he can secure a long-term contract with the club, League cup appearances are certainly within reach.

Which of these American prospects are you most excited about? Who do you think will make his first-team professional debut first?

Brian Sciaretta is an American Soccer Now columnist and an ASN 100 panelist. Follow him on Twitter.