Macari said: "It's a bit of a nightmare draw. No-one connected with the club wanted it.
"But it's a fantastic draw for the neutrals and it will be a fantastic event at Old Trafford and the Bernabeu. I just hope United can get through.
"The CV tells you that when Sir Alex does retire, Mourinho is capable of doing the job.
"Ronaldo will get a great reception because people remember what he was like when he came to the club.
"He wasn't a superstar but he worked hard on the training ground and he got better and better. When he left to go to Madrid, he was a fantastic player who had scored some fantastic goals for United."