As debate has intensified over the plan for the United Kingdom to leave the European Union, industries across Britain are preparing for a post-Brexit world. Along with the agriculture, automotive, pharmaceutical and financial services fields, there’s another prosperous British business that could feel the brunt of Brexit: the English Premier League.

From March 29 onward, all foreign soccer players — regardless of their origin — could require a work permit to sign for a club in the U.K. This would have enormous consequences for English clubs and the future of the English Premier League.

By separating from the EU, the U.K. will aim to end “freedom of movement of people” between the U.K. and EU — one of the four freedoms of the EU’s single market. For many years, freedom of movement has bestowed on citizens of the European Union (or the wider European Economic Area) the right to travel, reside and work in any member state. Because of this, a baker from Nice can open a shop in Manchester, a bond trader from Frankfurt can join a bank in London, and, yes, soccer players from continental Europe can freely transfer to the English league. If the player holds an EU passport, there are no restrictions: From an employment perspective, he is treated the same as a U.K. national.

Freedom of movement has had a seismic impact on the demographics of the league — all of which could change with Brexit. Prime Minister Theresa May has stated that freedom of movement will end when the U.K. leaves the EU, but she has yet to announce the new immigration rules that will replace it. Although EPL clubs will not immediately be required to obtain work permits for their players who aren’t British or Irish (citizens of the Republic of Ireland are likely to retain the rights to live and work in the U.K. post-Brexit), new arrivals from the EU could become subject to the rules that currently apply only to non-EU players. Essentially, all players not eligible for a U.K. (or Irish) passport would have to obtain a work permit.

To investigate the potential impact on English soccer, we took a look at the characteristics of European players who have played in the EPL over the past 26 years. What proportion of them would have qualified for a work permit? By answering this question, we can gain an insight into what might happen to the EPL in the future.

Before we can assess who might be affected, we first need to look at how the system of work permits works in English soccer. To obtain a permit, a foreign player must secure a Governing Body Endorsement from The Football Association (the governing body of English soccer). Each season, the FA publishes guidelines to help clubs determine whether transfer targets would qualify for an endorsement.

Share of senior competitive international matches required to qualify for an English soccer work permit endorsement National team’s FIFA ranking Min. share of matches played in past 24 months 1-10 30% 11-20 45 21-30 60 31-50 75 Players age 21 and younger may meet the senior match threshold in just 12 months. Source: The Football Association

There are effectively two paths by which a player can qualify. To automatically qualify, a player must have participated in a minimum share of his national team’s senior competitive matches in the preceding two years. The minimum percentage is determined by the FIFA world ranking of that nation.

If a player doesn’t qualify automatically, he can appeal. The appeals process is a points-based system that boils down to this: If the transfer fee is above the average amount paid by EPL clubs the previous year, and the club is willing to make him one of its higher earners, the appeals board can recommend that a permit should be approved.

In the early 1990s, a quota system was enforced for foreign players in English soccer that limited teams to fielding a maximum of three “foreigners” in domestic league and cup matches. A foreign player was defined as someone who held neither a U.K. nor an Irish passport. There was no distinction between players from Belgium and Brazil, even though Belgians had held the right to live and work in the U.K. for several years. Thirteen percent of the players that featured in the 1994-95 season were classified as foreign.

In December 1995, after the so-called Bosman ruling, the quota was rescinded, instantly removing all restrictions on fielding players from the rest of the EU. Clubs were still required to obtain work permits for non-EU players — a significant obstruction — but because of freedom of movement, the demand for soccer players with EU passports grew enormously. Cultural barriers aside, there were now no differences between recruiting a player from the Netherlands and one from Newcastle.

Over the past 20 years, the EU has expanded, bringing more countries into the “freedom of movement” area. The proportion of U.K. and Irish players in the EPL has continued to decrease: Last season, they accounted for only 41 percent of all EPL players. Players from the rest of the EU accounted for 41 percent, while non-EU players accounted for 18 percent.

From the inaugural 1992-93 EPL season to the end of last season, a total of 1,022 players have transferred to an EPL club from an EU club outside of the U.K. and Ireland and played at least one league match for that club. This includes players who played nationally for countries outside the EU but also possessed EU passports (such as André Ayew, who was born in France but plays for Ghana). Of the 1,022 players, we judge that only 431 — or 42 percent — would have qualified for a work permit under the current rules when they first arrived in England. Had they not held an EU passport, the remaining 591 players would not have been permitted to play professional soccer in the U.K.

What would be the consequences if, from next season onward, incoming players from the rest of the EU were subject to the same immigration requirements that currently apply only to non-EU players?

The figure above shows two future scenarios. The first is the status quo, in which EU passport holders can continue to play in the U.K. without work permits (or any other bureaucratic hurdles). The second explores the end of freedom of movement to the U.K. In this scenario, EU players are subject to the same immigration requirements as players from the rest of the world beginning with the 2019-20 season. That is, they require a work permit and must meet the relevant criteria.

In both cases, we assume that the total number of players in the EPL remains constant, as does the inflow and outflow of players from the rest of the world. In the status quo scenario, we assume that the inflow of players from Europe remains at its recent historical average; in the end of freedom of movement scenario, we assume that it drops to 42 percent of the recent average.

In the status quo scenario, the percentage of U.K. and Irish players remains close to its present value, gradually declining over the next decade. The proportion of players from the EU increases slightly, eventually exceeding U.K. and Irish players, while those from the rest of the world remains relatively constant.

The end of freedom of movement scenario paints a very different picture. The proportion of EU players declines substantially — from 41 percent last season to 20 percent by 2028-29 — while the proportion of British and Irish players increases from 41 percent to 64 percent over the same period. By the end of the next decade, the EPL would begin to resemble its constitution at the end of the 1990s: Nearly two-thirds of all players would be British or Irish.

A large drop in the number of EU/EEA players does not necessarily imply a substantial reduction in terms of the quality of players. The money and allure of the Premier League would still entice elite players to come to play in England, at least for a while. The wealthiest clubs would continue to attract the biggest stars; the rest, on the other hand, would be forced to focus more on the domestic market. Teams often scout for potential in soccer leagues across Europe, but many of those players would no longer be allowed to make the leap. Champions League places would move even further beyond the horizons of most clubs, and “near miracles” such as Leicester’s fairytale league win — on the strength of the star turn from Riyad Mahrez, who was acquired from Le Havre in France’s second tier — would become even less likely.

On the other hand, some will argue that a drop in foreign recruitment would be a positive thing if it affords greater opportunities to British players. While the situation would be unchanged in terms of top-end recruitment at the elite clubs, even they would be forced to review their recruitment of young players from abroad. Homegrown players might have more of a chance of making it at the highest level.

There is no doubt that the Premier League has benefited enormously from freedom of movement, with the rapid influx of foreign players helping to drive the league’s huge international popularity. But freedom of movement was also a crucial factor in the opposition to continued U.K. membership in the EU. It could well be that one effect of Brexit would be to diminish, perhaps sharply, the number of highly talented European footballers in the Premier League — which could have huge consequences for the future of the sport. ​

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