The United Kingdom opting to leave the European Union (EU) -- AKA Brexit -- represents a massive, momentous twist in European history. But does leaving the EU actually affect the Premier League? The answer is, largely, no. Though there are some significant twists and, perhaps, some opportunities as well.

The UK may have voted to leave, but it's not as if trade agreements and principles lapse overnight. It could take anywhere from two to 10 years to fully disengage from the EU -- we're in uncharted territory here, this has never happened before, so there's plenty of guesswork going on. You would imagine that the Football Association and the Premier League would look to keep things as they are for as long they can.

Right now, membership in the EU or its looser cousin the European Economic Area (EEA), commits a country to four "pillars," one of which is the free movement of labour. That means, simply put, that any citizen of an EU or EEA country can move to another and seek employment. It abolishes all discrimination against foreigners provided they are from either the EU or EEA.

If you're not from the EU or the EEA and you want to play professionally in Britain, you need a work permit and there are set criteria to obtain one. These have recently been updated but, broadly speaking, they're aimed at guaranteeing that whoever comes in is of a certain standard. (If you enjoy reading about this stuff, sports lawyer Daniel Geey wrote this helpful article.)

So, theoretically, once Britain leaves the EU, any non-British players would have to go through the work permit process. Some would not meet the criteria.

How many?

That's when things get a bit fuzzy. This article in The Guardian puts the number at 36, but that's under the old work permit regulations. The new ones are, supposedly, tougher but, as Geey's article shows, there are loopholes and exceptions. Even by a conservative estimate, we're talking maybe two or three guys per club who wouldn't make it in. And, most likely, they'd be the players sitting on the bench or in the stands.

There's another issue here. The vast majority of the pro-Brexit camp wants Britain to continue tariff-free trading with the EU on favored terms. That would mean either being part of the EEA (in which case they would still have to guarantee freedom of movement) or negotiating a deal whereby Britain could still impose strict immigration controls while enjoying free trade.

The latter option may be "unrealistic" and, indeed, it sounds a bit like wanting to have your cake and eat it too. Geey agrees, telling ESPN FC: "The UK would have to sign bi-lateral deals with every country and that would be very difficult and take a long time." That's because, among other things, the UK would essentially be saying "we can come to your house, but you can't come to ours."

But let's assume this is what happens. Britain somehow works out a deal to get the good bits of EU membership but also adds restrictions on labour. What then?

Well, that's when work permits would become an issue for European players. Not many, as we've seen, but some would be affected. Yet here's the thing: the work permit regulations aren't some devilish rules concocted by faceless bureaucrats. They're written by the British Home Office in conjunction with the Football Association, for the good of the English game. If, suddenly, English football -- and, especially, the Premier League -- were somehow significantly penalized by it, you'd imagine they could be re-written. Or, at the very least, we'd see a lot more "rubber-stamping" from the "Exceptions Panel."

So does this all mean Brexit won't matter to the Premier League?

Pretty much. Except, perhaps, for two other aspects which haven't been discussed much.

One concerns underage players. Article 19 of the Regulations on the Status and Transfer of Players bans the transfer of minors, defined as players under the age of 18. There are three exceptions. One: kids moving for non-football reasons (like a parent getting a job in a new country); two: youngsters residing near a border; and three: transfers of minors between the age of 16 and 18 within the EU or EEA.

Obviously, in the event of Brexit, that could not happen. That would mean that Manchester United could not have signed, for example, Adnan Januzaj of Belgium or Timothy Fosu-Mensah of Netherlands, or that, back in the day, Spain's Cesc Fabregas could not have left Barcelona for Arsenal.

Now, a number of European clubs -- not just in the Premier League, but elsewhere, too -- exploit a loophole in legislation allowing them to sign players when they turn 16, often with little or no compensation. That would become illegal.

Adnan Januzaj was one player who was signed at an early age. Matthew Ashton - AMA/Getty Images

The other twist in this -- and, given the might of the Premier League, it's unlikely -- is that English football could restore limits on the number of foreigners per team, like in the pre-Bosman era.

At present, limiting overseas players (from other EU countries) is illegal under EU law because it amounts to discrimination on the basis of nationality. But a post-Brexit Britain would have no such problems. The Football Association could, perhaps as a way to get English players more minutes on the pitch and help the national team, limit the number of foreigners to five (or fewer) per club.

That would have a huge impact. The bigger teams would raid the smaller ones for English players, whose transfer values would sky-rocket, and the smaller clubs would move down the food chain to the Championship and so on. But that would require a bunch of assumptions, like the FA having the clout to impose this on the Premier League. Frankly, it's farfetched.

So the bottom line is that while it may be fun to imagine the impact of Brexit on the Premier League, odds are it will be minimal, at least as far as senior players are concerned.