The former German international has stoked the fire ahead of the clash by claiming that Real Madrid are just a "normal" team.
"I have watched Real Madrid in the Champions League, and they only use standard equipment," said Beckenbauer.
"They are a great team and work efficiently, but are just normal. Then there is the incredible dimension that Barcelona operate in."
Beckenbauer played for Bayern Munich between 1964 and 1977, while also enjoying two stints as manager in 1994 and 1996.