Messi was heavily linked with a move away from the Camp Nou ahead of the 2020/21 season as the Argentinian international entered into the final year of his contract in Catalonia.
Despite the fervent speculation, Messi confirmed he would remain at the club and see out his contract, with the potential of signing an extension in 2021.
However, his form this season has been indifferent with four goals from nine league games.
Ronald Koeman has defended his skipper’s mixed goal scoring run, stating he is an ‘easy culprit’ for Barcelona’s struggles, but Pirlo believes there is still an issue with Messi.
“He is at a special moment in his life, not just in his career, because he had a problem this summer,” as per reports from Marca.
“Whether he stayed at Barça or not, during games he has always shown his value.
“More than football, he probably has a problem mentally, but I don’t want to go into it, it’s not our place.
“Messi is a phenomenon and he has always shown that.”
Barcelona take on Juventus in their final Champions League group game on December 8, with Koeman’s side on the brink of confirming top spot in Group G.
Messi is likely to be rested for the visit of the defending Serie A champions, after being omitted from the matchday squad for Barcelona’s last two Champions League games, with highly rated La Masia graduate Konrad De La Fuente set to partner Martin Braithwaite.