Former Barcelona and Real Madrid defender Luis Milla has said Lionel Messi is the "only substantial difference" between the El Clasico rivals as they meet twice in four days.
Los Blancos host the Blaugrana on Wednesday in the second leg of the Copa del Rey semi-final with the score tied at 1-1, but then welcome Barca again in La Liga on Saturday.
Speaking to Ignasi Oliva Gispert of Goal ahead of the cup match, Milla said neither team are currently at their vintage best.
"I don't think there's a favourite, even if one side comes into it in better form than the other.