Lionel Messi risks a FIFA ban if he leaves Barcelona without resolving his contractual dispute, a leading sports lawyer has claimed.
Messi has handed in a transfer request and remains under contract until the summer of 2021.
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Nick De Marco QC, who has represented sport's governing bodies, players, clubs and agents since 2002, says world football's governing body is likely to be asked to settle any dispute in the first instance.
"If it ended up anywhere, it would be most likely in the FIFA Dispute Resolution Chamber because Messi, being Argentinian, the FIFA rules would apply, and FIFA has its own set of laws and rules," De Marco, of Blackstone Chambers, told The Transfer Show on Sky Sports News.
"So, it's unlikely to be Spanish law or English law or Swiss law but it would be the FIFA rules that apply, and they have a commission that can determine these things.
"Ultimately, either party can then appeal to the Court of Arbitration for Sport. That's how these sorts of issues are normally dealt with.
"One possibility, and it's certainly not one I'm advising anybody, is a player simply just walks out and says, 'I'm entitled to walk out, so I'm walking out'.
"The risk with that strategy is, although FIFA will normally allow the registration to move with the player, if the club then brings a claim and succeeds, not only is the player liable to [pay] damages but also is likely to be banned under FIFA rules for a period of months and the new club signing him have a transfer embargo.
"It's such a high-risk strategy that, unless you were sure that the player was in the right, it's not a risk one would take."
De Marco, who is not representing Messi or Barcelona, and has no visibility over their contracts, believes a "commercial solution" is likely to be found.
"You have to read the contract as a whole," he explains.
"Even if it's a date, and the date is the date, if that's linked to other provisions that show what the parties really meant was the end of the season, then there's still an argument it's the end of the season.
"There are legal arguments on both sides but in my experience, in ninety-five per cent of these types of cases, you find a commercial solution.
"The last thing that Barcelona want is a player who's not fully committed and drawing those wages. It's not only bad for him, it's bad for the whole dressing room.
"The last thing a player like Messi wants is just to sit there and receive money without playing. For a player of his stature, and genius, he wants to be succeeding and, so, it's in the interests of both parties to work this out and come to a sensible compromise."
What is Messi's current contract status?
One thing that is crystal clear at this stage is Messi remains contracted to Barcelona until the summer of 2021.
The 33-year-old signed a four-year contract back in November 2017, a deal he claimed made his dream of finishing his career at his "home" Barcelona a reality.
"I'm happy to continue with the club, which is my home. My dream was to finish my career at Barca and we are moving down that path," he said three years ago.
Inserted into Messi's contract was a staggering 700 million euro (£626m) buy-out clause that would-be suitors would have to pay in order to lure him away from the Nou Camp.
The clause, coupled with Messi's commitment on renewal, seemed to make a Barcelona exit financially and emotionally unviable, but this week's incredible developments mean it is now more possible than anyone could have imagined.
What about Messi's exit option?
Also inserted into Messi's contract back in 2017 was a clause that states he could leave Barcelona for free at the end of every season should he wish, as Spanish football expert Graham Hunter explains.
"When Messi's last contract was signed, his camp argued for a 'get-out-of-jail free' clause at the end of every season," he told The Transfer Show.
"He had to inform the club in May that he wanted to leave, and they had to allow him to leave for nothing.
"Messi and his people have been prepared to parachute out of a failing football club for a very long time.
"When that clause was inserted it was typical of this club, that they can be told something in big, bold writing and misunderstand it or fail to act on it - just look at the Neymar fiasco."
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The summer transfer window will run for 10 weeks from July 27 and close at 11pm on October 5.
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