Ghana star Michael Essien was in action on Tuesday night as counter-attacking Real Madrid dismantled Barcelona 3-1 at the Nou Camp to reach the Copa del Rey final, sealing a 4-2 victory over the two legs.
Ronaldo scored a first-half penalty, then a second just before the hour to leave the Liga leaders with a huge task.
And Raphael Varane, who struck in the first leg, added a header to all but kill off the tie.
Barcelona dominated possession but were dominated everywhere else, with Lionel Messi conspicuous by his absence in a rare poor game.
The hosts did add a super goal in the 89th minute, Jordi Alba tucking away Andres Iniesta’s through ball on the volley, but as well-taken as it was, it represented scant consolation.
Real Madrid go into their 38th Copa del Rey final, where they will face either Atletico Madrid or Sevilla, depending on the result of their second leg tie on Wednesday.
Barcelona may have the league virtually sewn up, but their hopes of a treble are over, and their all-conquering season is in danger of taking a major hit, with the team needing to overturn a two-goal deficit against AC Milan to reach the Champions League quarter-finals.
And confidence in the Blaugrana ranks cannot fail to have taken a hit ahead of another Clasico on Saturday, this time at the Bernabeu in the league.
Both sides made seven changes to their line-ups after victories in La Liga at the weekend, meaning that both were at full strength for the tussle.