The two clubs have been kept apart until the Champions League final.
A meeting with Pep Guardiola's men is something Ferguson would relish, even though old friend Harry Redknapp has labelled them the best club side ever.
"Hopefully they have reached their peak already," said Ferguson.
"They are an example to everyone of how to play football.
"People say they don't want to play against them. I think it is a privilege.
"It is the kind of challenge you want."