THIS weekend Major League Soccer will experience its first-ever New York derby in the playoffs as New York City FC and New York Red Bulls face off in an Eastern Conference semifinal.

Such a clash has been a possibility since New York City joined the league in 2015, but though the teams have met regularly in the league and in other competitions, they have avoided each other in the post-season competition that determines the MLS champions — until now.

This fixture is also more than just a local rivalry between teams bearing the New York name. It is a meeting of the two highest-profile multi-club ownership groups in world football and one which has numerous local implications and storylines.

The fact New Yorks City and Red Bulls are owned by multi-club entities can take away some of their local identity, their New Yorkness, and in the Red Bulls' case, also their New Jersey-ness.

Given MLS teams are all centrally owned by the league, these New York teams are franchises both in an American sports sense and in a business sense as part of their parent companies whose flagship teams are based elsewhere. It poses a double whammy of obstacles when it comes to forging a unique local identity.

Fans, supporter groups and some team staff have worked hard within these restrictions to create a culture at each of these franchises, attempting to forge some kind of identity away from the uniform (in two senses of the word) branding of their multi-club ownership groups and that of MLS itself.

Prior to their takeover by the Austrian energy drinks company in 2006, the Red Bulls were known as the MetroStars. It was an ideal name for an original team that joined the league for its inaugural season in 1996, encompassing not just New York City, but the wider New York Metropolitan area.

This gave the Metrostars the potential to draw a fanbase from anywhere in the Tri-State area of New York, New Jersey, and Connecticut, and even into Pennsylvania.

This is why, in those early days of MLS, the MetroStars’ biggest rivals were DC United down in Washington DC.

There was no MLS team in Pennsylvania until Philadelphia Union entered the league in 2010, and there was no local New York area rival until City entered the league in 2015.

It gave the MetroStars an early footing in a soccer-rich area and many long-time MLS fans and soccer reporters from this region still have an affinity to them.

The arrival of New York City created an immediate rivalry due to the proximity of the teams.

It is named the Hudson River Derby after the river which separates New York City (where City play) and New Jersey (where Red Bulls play in Harrison, near Newark).

Since joining MLS 10 seasons ago, New York City have never had a home to call their own. This is something Red Bulls fans have delighted in pointing out whenever they can. In response, City fans will often remind the Red Bulls that they play in New Jersey, not New York.

The majority of New York City’s home games across the years have been played at Yankee Stadium, home of the New York Yankees Major League Baseball team.

Others have been played at Citi Field, home of another MLB team, the New York Mets, and this is where this weekend's Eastern Conference semi-final will take place because, funnily enough, there is an American football college game being played at Yankee Stadium.

Some of City’s home matches have even taken place at the stadium of their rivals at Red Bull Arena in Harrison, which has added yet another angle to this rivalry.

This will all change in 2027 when the construction of a soccer-specific stadium in the Willets Point area of Queens is due to be completed and New York City will play their first season in a home they can call their own.

This week, the inevitable announcement was made that this stadium will be sponsored by Etihad Airways, just like the stadium of City Football Group’s flagship team, Manchester City.

Though Etihad Park will be emblazoned around the place, again, supporters are looking to build their club’s identity themselves and have other ideas as to what they will refer to it as.

Much of this is based on the history of Willets Point, and some of it on references to the region in F Scott Fitzgerald’s 1925 novel, The Great Gatsby.

In The Great Gatsby, the area of Flushing Meadows and Willets Point is referred to as the Valley of Ashes, which is what many fans have already taken to calling the new stadium complex. There are already numerous ideas of how to incorporate this into supporter culture in the stands which will be refined in the next few years.

The area is also nicknamed the Iron Triangle in reference to the array of chop shops, auto repair shops, and junkyards — businesses that survived against the odds —  in the area.

Many of the people running those businesses had to relocate to make way for numerous previously planned developments that never came to fruition, but the remnants of the Iron Triangle could be seen until very recently, with some automobile shops still operating.

This is another part of local history New York City fans could adopt, and the Iron Triangle makes for a strong industrial name and a link to football’s working-class roots.

Playing on the team’s history of playing in baseball stadiums in some way would also pay tribute to their formation and early years. After all, games played on American football and baseball fields are a unique part of American soccer culture and New York City have enjoyed, or endured, plenty of this.

There are more strands to a Hudson River derby than meets the eye, from multi-club ownership to local sporting and wider social history, but this game will be defined by two sets of fans and the New York Metropolitan area football clubs they, more than anyone else, have created out of a valley of franchises.