The two have struck it off since Fernandes arrived at United in January, with Mata previously saying they "understand football in the same way".
There is no doubt Fernandes has settled on the pitch at Old Trafford, with three goals and four assists in six weeks of footbll, and his friendship with Mata has helped him off the pitch too.
Asked which team-mate he'd isolate with, Fernandes told Manchester United's official website: “I would choose Juan, because if I isolate with Juan I can listen to my song all day, every day! He always sings it to me!"
"It’s not the atmosphere of Old Trafford, but Juan is the kind of guy who puts all his heart in the song, so when he sings the music for me is really nice!"
The United chant Fernandes refers to describes him as the "Portuguese magnifico" and is sung to the tune of the 'follow, follow, follow' song.
The January signing added: "Normally I arrive before him [Mata], and he comes at breakfast, gives me his hand and starts to sing the song – Bruno, Bruno, Bruno!”