Lionel Messi's contract leak: All that you need to know

Spain's El Mundo newspaper claimed it had access to the document Messi signed with Barcelona in 2017, which included fixed incomes and extras that could reach nearly €138m (£122m) each season.

It is thought to be the biggest pay deal ever for an athlete.

Notably, Messi would have to pay about half of that amount in taxes in Spain.

According to a report in ESPN, both Barcelona and Messi are expected to take legal action against the Spanish outlet which released the leaked details of the Argentine's record-breaking contract.

There are only four copies of the contract. Messi has one, Barcelona have another, the Spanish league has a copy and so does Cuatrecasas, the law firm used by the Argentine.

"In view of the information published today El Mundo, in relation to the professional contract signed between FC Barcelona and the player Lionel Messi, the club regrets its publication given that it is a private document governed by the principle of confidentiality between the parties," the Catalan club said in a statement.

Barcelona denied any responsibility for the publication and said legal action will be taken.

"FC Barcelona categorically denies any responsibility for the publication of this document, and will take appropriate legal action against the newspaper El Mundo, for any damage that may be caused as a result of this publication."

Barca expressed their support for Messi, especially in the face of any attempt to discredit his image.

Manager Ronald Koeman said the leak was "was [done] with malicious intent to do damage."

"More respect should be shown to a player that's given so much to Spanish football. We must try and find out how the contract's come out in the press," he said.

Messi's future at the club beyond the 2020-21 season remains unknown. The senior player tried to leave the club last summer but was shut down by then-president Josep Maria Bartomeu.

In a recent interview, he stated that he has not yet made a decision on his future and will decide his next step when the season ends.

The report in ESPN added that negotiations over a new deal will not be able to begin until March and the new terms will have to correspond with the Barca's new financial position.

The club's annual accounts, dated August 2020, revealed earlier this month that Barcelona's gross debt have risen to nearly €1.2 billion.