Lionel Messi is "from another world" and near impossible to defend against, according to former Real Madrid star Rafael van der Vaart.
Real meet Messi's Barcelona at the Santiago Bernabeu on Wednesday in the second leg of their Copa del Rey semi-final.
The tie is finely balanced at 1-1, and the winner will set up a final clash against either Valencia or Real Betis.
Los Blancos go into the fixture on the back of a 2-1 win over Levante in La Liga that followed a shock defeat to Girona at home.