Messi, who has cemented a legacy as one of the greatest players in football history at the Nou Camp, was recently accused of implementing a “regime of terror” in Barca training by Griezmann’s former agent Eric Olhats.
The France international’s uncle also weighed in on the argument, suggesting training sessions in Catalonia are designed purposely to please Messi.
“[Griezmann] was convinced that he wasn’t going to be successful within the first six months, but what I didn’t expect was that it would last an entire year,” Emmanuel Lopes told El Chiringuito.
“Besides, with Messi, I know what’s going on inside [the club] – it’s not easy.
“Basically, [Messi] doesn’t work hard enough at Barca and the training sessions are structured in order to please certain people, which is fine if you don’t want to work [as hard].”
Antoine needs to work, even though others don't need as much effort to play well.
“He's the other way around - he needs to put in a lot of effort for himself."
But after landing back in Barcelona from international duty with Argentina, Messi hit back at Lopes and Olhats’ accusations and told reporters he is “tired of always being the problem”.
The 33-year-old said: “The truth is that I'm tired of always being the problem of everything at the club.”
Griezmann endured a frustrating debut season at Barca last season after sealing a £107million move from Atletico Madrid, scoring 15 goals in 48 appearances for the Catalans.
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When recently quizzed on his relationship with Messi, the forward said: “It has been similar to me relationship with [Kylian] Mbappe, at first we did not meet through the passes and it took me a long time to get along with him.
“With Messi everything will be better”.