Barcelona are on the brink of losing Lionel Messi this summer.

The club's all-time top scorer dropped a bombshell on Tuesday night by submitting a transfer request, claiming that a clause in his contract would allow him to leave for free in 2020.

And while Barcelona armour up for a legal battle that, at best, would keep Messi on their books for another season, many of Europe's top clubs are running the maths on how they could sign him.

Messi's Barcelona legacy

On the one hand, the prospect of one of the greatest footballers of all time plying his trade in the Premier League or Serie A after so many years is undoubtedly exciting.

But on the other hand, you can't help feeling a tinge of sadness that one of the finest player-club collaborations in the history of sport could be coming to an end in such unsavoury circumstances.

Besides, if we were to outline everything that Messi has achieved in his 16 years as a first-team player in Catalonia, this article would be long enough to qualify as a novel or textbook.

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Incredible memories at Camp Nou

However, although some Barca fans will inevitably be angry at Messi's behaviour, there can be no denying the Argentine's loyalty to the club throughout his career in the beautiful game.

Even if Messi has scored his last goal for the club, he has still appeared 731 times in Barcelona colours, second only to Xavi, while also scoring on a mind-boggling 634 occasions.

So, sure, Messi might not go down in the history books as a one-club man, but don't think for a second that he isn't one of the most loyal players of the modern era regardless.

And if you still don't believe us then Transfermarkt have put Messi's situation into perspective by highlighting the 15 most loyal players to their current club in Europe's top 10 leagues.

Lionel Messi for Barcelona in 2004.

Most loyal players in Europe's top 10 clubs

In fact, it highlights that only one player has continually featured for their current employers longer than Messi - and you can check out who that is, as well as the other 13 stars, down below:

15. Marcel Schmelzer (Borussia Dortmund)

Time at the club: 13 years, 1 month and 25 days

14. Sergio Busquets (Barcelona)

Time at the club: 13 years, 1 month and 26 days

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13. Andriy Pyatov (Shakhtar Donetsk)

Time at the club: 13 years, 7 months and 25 days

12. Anton Shunin (Dinamo Moscow)

Time at the club: 13 years, 7 months and 25 days

11. Marcelo (Real Madrid)

Time at the club: 13 years, 7 months and 25 days

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10. Sammy Bossut (Zulte Waregem)

Time at the club: 14 years, 1 month and 26 days

9. Sergio Ramos (Real Madrid)

Time at the club: 14 years, 11 months and 26 days

8. Giorgio Chiellini (Juventus)

Time at the club: 15 years, 1 month and 26 days

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7. Francesco Magnanelli (Sassuolo)

Time at the club: 15 years, 1 month and 26 days

6. Jessy Moulin (Saint-Etienne)

Time at the club: 15 years, 1 month and 26 days

5. Oier (Osasuna)

Time at the club: 15 years, 1 months and 26 days

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4. Sergio Alvarez (Celta Vigo)

Time at the club: 16 years, 1 month and 26 days

3. Mark Noble (West Ham United)

Time at the club: 16 years, 7 months and 25 days

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2. Lionel Messi (Barcelona)

Time at the club: 16 years, 7 months and 25 days

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1. Igor Akinfeev (CSKA Moscow)

Time at the club: 17 years, 7 months and 25 days

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Time to end the loyalty?

So, say what you like about Messi potentially jumping ship, but he's given 16 and a half brilliant years to the Barcelona faithful and that's the positive that fans should hold on to right now.

You only have to watch the footage of supporters outside Camp Nou to get an idea of just how much Messi leaving means to the city community - and any exit will send global reverberations.

But, you know what they say, all good things come to an end. You've just got to treasure the memories Messi has left behind and in his defence, he's left thousands and thousands of them.

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