Real hammered the Bundesliga side 9-2 on aggregate at the same stage of last year's competition en route to being crowned European champions for a 10th time.
The tie was over after a sensational first leg, in which Cristiano Ronaldo and Karim Benzema each scored twice in a 6-1 thrashing at the Veltins-Arena.
Ronaldo also helped himself to a double in the second leg at Santiago Bernabeu as Carlo Ancelotti's men finished off the job with ease.
Butragueno, the Spanish giants' director of institutional relations, expects the La Liga leaders to progress to the quarter-finals, but does not envisage Schalke to make life easy for Ancelotti's side.
He told the club's official website: "Our view about the draw is an optimistic one. We have the great experience of last year, when we practically decided the tie in the first leg, but we know that football can be cruel and it will be harder this year. We have to be cautious.
"They are very competitive and have a loyal fanbase. We'll have to try for a similar result to last year's in order to kill things off in Madrid. There were tougher opponents theoretically, but 90 minutes in Germany will be difficult.
"A lapse of concentration can cost you dearly. As such, we have the upmost respect for the opposition, a club we have a strong relationship with."
The first leg will be played in Gelsenkirchen on February 18, with the return fixture held in Madrid on March 10.
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