Messi signed a new contract with the Catalan club in November after months of speculation over his long-term future.
El Mundo have reported that the delay to his new contract was not purely because of the financial negotiations, but because of the political crisis in Catalonia over their recent independence vote.
However, the sums involved in his deal are staggering, if as claimed. The contract runs until 2021, with the option of another year for Barcelona.
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After Messi's conviction for tax fraud, he has apparently been handed a signing-on sum of €100m (£88.5m) as compensation for his troubles.
Beyond that, he will earn €70m a year in wages, around £1.2m a week, and he has been granted exclusive image rights.
The total cost of the deal comes to €450m, and will earn Messi €3,995 an hour, which works out as almost €100,000 a day after tax.
The figures represent a deal that is 70% more lucrative that Cristiano Ronaldo's current deal with Real Madrid, and only €4m a year worse than Neymar, who joined Paris Saint-Germain this summer.
Image credit: Getty Images
Other sporting figures have also been left behind. Steph Curry earns €40.5m a year, and Fernando Alonso €37.7m. The only other footballer to come close to his salary is Carlos Tevez, whose deal in China is worth €64m each year.
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