Lionel Messi and Barcelona aren’t going to take the leak of the superstar’s massive contract lying down.

Both the club and player will take legal action against the Spanish newspaper El Mundo, which on Sunday published the details of the four-year pact that Messi, who is widely considered the greatest player of all time, signed with the Spanish titan in 2017.

The deal is worth a whopping $674 million — easily the richest in professional sports.

In a strongly worded statement released shortly after the story rocketed around the world, Barcelona denied leaking the document to the outlet while also announcing its intention to sue.

“In view of the information published today in the newspaper 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 statement read.

It added that the club “will take appropriate legal action against El Mundo for any damage that may be caused as a result of this publication.”

Separate from any lawsuit Barcelona may file against the paper, Messi’s attorneys are also expected to seek damages on behalf of their client, according to ESPN. That report stated that only four parties have copies of the contract: Messi, his law firm, Barcelona and La Liga.

The revelation of the otherworldly compensation Messi receives — it dwarfs the North American-record $503 million, 10-year agreement Kansas City Chiefs quarterback Patrick Mahomes inked last year — comes after a sharp downturn in Barcelona’s form and finances in recent seasons. As such, El Mundo’s report was understandably the talk of the soccer world on Sunday. But the white-hot scrutiny and the looming legal drama didn’t appear to cause any distractions for the 33-year-old Argentine when he took the field just hours later.

On the contrary; Messi, who unsuccessfully attempted to force his way out of Barcelona last summer, enjoyed perhaps his best performance of the 2020-21 season in Sunday night’s 2-1 league win over Athletic Bilbao.

Messi, who was red-carded against Bilbao two weeks ago as Barcelona was upset in the Spanish Super Cup final, opened the scoring at the Camp Nou off one of his trademark left-footed banana kicks:

The visitors pulled even early in the second half through an own goal by Jordi Alba, but Antoine Griezmann broke the tie to help Barcelona exact a small measure of revenge and leapfrog chief rival Real Madrid and into second place.

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