Maradona featured for both Barcelona and Napoli in his illustrious career, but he's made it clear that he's backing the Italians.
The Argentinian icon has cult-hero status in Naples, where he is viewed as a footballing god.
Maradona feels empathy for his compatriot Messi, who he feels suffers from an immense amount of pressure.
"Leo is a great talent, a very good boy, but they want him to carry unfair amounts of pressure," Maradona explained in an interview with Il Mattino (via Marca).
"He has to live his life and career knowing he is the best footballer, yet there have been comparisons for almost 20 years, what is there to compare?"
Maradona claims that he shares a good relationship with Messi, but he hopes he fails against Napoli in the Champions League.
"I have a beautiful memory of working with him with the national team, but I just hope he doesn't play well against Napoli," he said.
"I gave everything to Napoli, and Napoli gave me everything.
"The match against Barcelona will be very difficult, but I have hopes that they will surprise me and give the fans a huge feeling of joy.
"I have a great love for Napoli, I had magnificent years with them, we won the title and the UEFA Cup, whilst I also won the World Cup."
When Maradona was pressed on his allegiances, he made it very clear who he stood behind ahead of the first-leg.
"Barcelona opened the doors of Europe to me, but I wrote my story in blue, my heart is with Napoli," Maradona affirmed.
"I was with Boca, a great club, and came to Europe with Barcelona.
"It was a dream for all Argentine footballers, but there I had to face many problems."
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