Cluj keeper Felgueiras was junior teammate of Man Utd star Nani
Nani played with the keeper as a schoolboy at Sporting Lisbon when the pair visited the Theatre of Dreams together.
The stopper, 25, said: "I came to visit the stadium. Coming back is a dream.
"Nani proved what a good player he is here.
"It is possible we would only beat Manchester United once in 15 games. But it could be now."