Ronaldo will face the Red Devils for the first time since completing a world-record £80m switch to the Bernabéu in 2009, with United travelling to the Spanish capital for the first leg of the last-16 encounter.
The 28-year-old has impressed for Madrid in recent weeks, scoring a hat-trick against Sevilla on Saturday, but Ferdinand is hoping Ronaldo will be fazed by the enormity of the occasion.
“It’s obviously going to be an emotional night for Ronaldo and a great night for him too,” said Ferdinand. “But hopefully it gets too emotional for him.
“We’ve had a few texts, but when you get into a situation like this when you’re coming up against a friend, all the texts and the conversations go to one side and you don’t really speak until you actually get the game over and done with.
“He has a great rapport with the fans and there is a mutual respect between them both, which is great.
“The fans appreciated him when he was here and since he’s been gone they sing his name. He came here a young boy and left a world-class player. He showed a lot of respect when he left and still does.
“We’re going to have to use all of our experience, courage and ability to make sure that we stop not only Ronaldo, but the other players they have, because Real are a great team.
“They have so many other weapons. We could shut Ronaldo down for 90 minutes, but they still have players to hurt us, so we have to be compact and work hard.”