Santiago Solari's side hold the advantage after they won the first leg of their quarter-final 4-2 at the Santiago Bernabeu on 24th January.
Real have won five, drawn one and lost two of their games since the mid-season break.
They are 10 points behind fierce rivals Barcelona in La Liga, and so winning the Copa del Rey and securing a fourth consecutive UEFA Champions League title serve as the main priorities.
Gareth Bale, who returned from injury to score and help Real win 4-2 at Espanyol on Sunday, could be in line to start, although captain Sergio Ramos is a doubt after he came off at half-time in that match.
Despite picking up a red card against Espanyol, Raphael Varane is available for the Girona game.
