Guardiola confirmed the French defender was in Barcelona on Thursday after treatment on a knee injury, which has been forced to miss the last three months of the season.
Guardiola added: "Wow I didn't know that. Fuck, he's a lucky guy!"
'He's injured, it's not easy - meniscus. "I don't know. I have to install an Instagram account because I didn't know".
On reporter's inquiry about Mendy, who is now recovering from a knee ligament injury that has sidelined him since November, Guardiola laughed at the report and even queried a club press officer to see if he had any ideas. "You have to know!" to which the club official said he didn't. "No it's definitely not OK for him to be so far way".
Mendy has gained a large following - he has 1.13 million Twitter followers and 2.6 million followers on Instagram - thanks to his humorous personality.
Mendy then took to Twitter and claimed it was a joke.
Mendy continued the joke with another Instagram Story post showing him at Manchester airport with the location tag "Dubai Mall Burj Khalifa".
The Frenchman had been in Barcelona recuperating from a knee cartilage injury but posed a video on social media claiming to be in the far east.
Guardiola, however, was caught by surprise when a reporter brought this to his attention, but appeared to see the amusing side.
The former Barcelona boss warned the full-back in August that he needed to forget about the internet and focus on his football as he looked to put an injury-hit first season with the English champions behind him.
So, it seems like Mendy might be okay with his manager.
'It's a final for us, and we have to play it in that way, ' he said.
"Every player understands this". The manager is the manager.
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