The Spanish champions head to Old Trafford on Tuesday for the Round of 16 second leg following the 1-1 draw in Madrid and the former Liverpool midfielder is preparing himself for a special occasion.
"From the fans' point of view and because of the history of both clubs, this meeting is pure football," he told Champions Matchday magazine.
"For Cristiano (Ronaldo), who wore the United shirt for many years, it is something even more special. It is for me too.
"When I played for Liverpool, the games against United were very intense and important due to the rivalry that existed between the clubs.
"We know it is now a few years since Real Madrid won its last European title, but it is not easy to win this competition because we are facing the best teams in Europe.
"It doesn't have to become an obsession because this doesn't help, but, yes, it is an important objective."