Although precise legislation restricting the inflow of workers from Europe is yet to be written -- and unlikely to come into effect before July 2018 -- the UK's decision to part ways with the continent will likely mean English clubs will see fewer bargain players like Riyad Mahrez and N'Golo Kanté, two key drivers to Leicester's seemingly impossible success story.
"Those foreign players add a lot to our league -- a heck of a lot," former England international Owen Hargreaves, a Canada-born midfielder who played at Bayern Munich for seven years before joining Manchester United, tells CNN.
"Maybe Mahrez and maybe Kante wouldn't have played in the Premier League, because they weren't superstars," he adds, alluding to new rules which could place restrictions on signing players who haven't played for top-ranked national teams.
Once Britain's demarcation from the EU is finally drawn, footballers looking to ply their trade in the UK are likely to be subject to a similar set of rules that govern transfers from outside the region (assuming Britain does not appeal for a quasi-European open border scheme modeled after Switzerland and Norway, which appears unlikely
considering remarks made by new prime minister Theresa May).
Those rules were tightened last year under English Football Association chairman Greg Dyke's plan
to limit player inflow and give more first-team chances to homegrown footballers. Dyke's tenure as FA chairman ends this month.
Currently, players from outside the EU must either meet a minimum number of international appearances for a top-50 country over the previous two years (the higher the ranking, the less number of matches necessary), or a club must appeal by demonstrating that a player is special enough to warrant a visa by paying him annual wages far above the league average, which stands near £1.7 million
Mahrez was bought reportedly for just £425,000 ($550,000) from French tier two team Le Havre in January 2014 and blossomed into PFA Player of the Year in 2016 thanks to his 17 goals and 10 assists.
Born in France, he made his international debut for Algeria -- a top-50 team since 2009 -- ahead of the 2014 World Cup in Brazil, where he featured in just one match.
Kante, a defensive midfielder, was purchased for a reported £5.6 million ($7.26 million) in August 2015. He made his debut for France in March 2016 and was part of the squad that reached the final at Euro 2016. Kante has just signed for Chelsea in a deal worth a reported $39.5 million.
In all, an estimated 135 first-team Premier League players from Europe would have a tough time qualifying if broader rules were previously in place, according to the New York Times.
Notable examples are two of Manchester United's key players, Anthony Martial and David de Gea, who were signed before becoming established members of the senior France and Spain squads.
That could be bad news for a league that has historically embraced the technique and skill that European footballers have brought to the Premier League.
Hargreaves notes that European players he grew up watching were also instrumental in introducing diet and fitness into the English game, where long boozing sessions after matches were not uncommon.
"The Premier League has always had the quality (foreign) individuals; your (Eric) Cantonas and your (Dennis) Bergkamps and (Thierry) Henrys, and I think it's important because they changed the game here.
"(Arsenal manager Arsene) Wenger and Bergkamp changed that, and I think it's important that you have those people come over who influence football."
It's not surprising then that Wenger -- the Frenchman largely responsible for Europe's initial influx into the Premier League -- agrees.
"It worries me. It shocks me too," he said to France Football
following the UK's EU referendum on June 23, the results of which immediately led to the resignation of Prime Minister David Cameron. "Currently the (Premier) League is seen as the most attractive one and that image could disappear."
'Football will be gone in five years'
Wenger notes that along with future restrictions on player transfers, a weaker British pound -- which dropped to its lowest level in 30 years against the dollar following the Brexit announcement -- creates a competitive disadvantage for English clubs that could have long-term repercussions.
"The players are going to see their salaries drop a little bit and the competition with Germany, for example, is going to be stronger," he said.
"If the league becomes less attractive the broadcasters will offer less money for the rights, club revenues will decrease, and the Premier League will suffer the consequences. There lies the problem."
Currently, 17 of the top 30 richest football clubs in the world are in the Premier League, according to Deloitte, mainly because of TV rights deals which are distributed evenly, worth about £1.62 billion ($2.1 billion) next season alone.
The stakes are so high, some say, that changes can't possibly be enforced without some concessions by the Football Association.
"I just can't see it going through, everybody has too much to lose," says football agent Barry Silkman, who represents 11 Premier League players, all of them foreign bar one.
Silkman adds that the threat of lost TV revenue would spur the top Premier League teams to form an alliance and structure their own deals.
"If that happens, football (in Britain) will be gone in five years," he says. "It would all be over."
But Andrew Osbourne, an immigration lawyer at Lewis Silkin who specializes in sports transfers for the likes of Arsenal and Chelsea, says it is unlikely for the UK to create a separate category that grants exceptions for European athletes to bypass work visa restrictions.
"The government would be very cautious about creating an industry specific scheme, because that opens the door for every other industry to go petition for their own scheme," he explains. "They don't have the resources for that."
Remarkably, however, Osbourne has yet to field many enquiries on the potential gravity of Brexit's fallout from football clubs -- partly because staffers are just returning from vacations, but also due to the long-standing belief that they are somehow immune to the bigger picture.
"Premier League teams tend to think they can just throw money at the problem, and they have plenty of that," says Osbourne.
Loopholes will shut
But money aside, Wenger and co. will also feel the pinch with the likely removal of a loophole that currently allows youth academy players to transfer within the bloc before they turn 18.
That's how Arsenal was able to sign current and former stars Hector Bellerin and Cesc Fabregas from the Barcelona youth academy at 16.
"That's where the biggest impact will be felt," says Osbourne. "A lot of big clubs in this country have recruited heavily from the EU; Europe has become part of their scouting market and they have pulled over a lot of 16 and 17-year-old players."
Ultimately, all these potential restrictions have the ability to inflate costs and compromise the Premier League's global competitiveness.
"If you have a more scarce supply then you will get price inflation," adds Osbourne. "For the players you know you can get in, you'll be paying bigger fees and bigger wages on them.
"It is going to be the players who are not the high profile internationals (that will be impacted the most). The top Brazilian internationals or Argentinians, they will come, but if you have a guy who played for Slovakia twice, he probably won't come now."
It appears inevitable that British players will see more action in the nation's top leagues down the road. That is why certain so-called Brexiters, like Sol Campbell -- who was one of only two regular British players on the Arsenal's "Invincibles" squad of 2004 -- wanted Britain out of the EU.
"The Premier League is in danger of becoming a free-for-all because, along with the star players, we are seeing teams load up with too many mediocre overseas footballers, especially from Europe, crowding out young English and British talent," he wrote before the vote in a column for the Mail on Sunday.
"Because of European rules on freedom of movement, it is virtually impossible for us to get a proper grip on the situation."
There are no guarantees, however, that the talent pool will remain as high.
"From a numbers point of view there will be more opportunities for local players, but the thing about sport is it's all about competition and driving performance up," says Osbourne.
"So if you have opportunity but you don't lose quality then that's great -- but the concern is that if you have a smaller pool (of foreigners) then quality is diluted.
"There will be much more local focus but will those players get to that same level? That's an unknown."
But Silkman, who enjoyed a long playing career in England before becoming an agent in 1987 and brokering an inflow of foreign talent, is less equivocal.
"It's total nonsense. It will get worse, it has to," he says. "What do they think, that all of a sudden all these players are going to spring up from out of nowhere?"