The 28-year-old has never faced the Premier League leaders since his departure in the summer of 2009 to the Spanish capital for £80m.
"Cristiano is ready for United. He's very excited, he wants to play right now. There's a lot of anticipation about going up against his former team for the first time. He's ready," Essien told reporters.
Loanee Essien himself is also no stranger to United, having played against the Red Devils on numerous occasions during his spell with parent club Chelsea.