Ramos, who has struggled with a number of issues in recent months, has not been included in the squad against his former club, having been diagnosed with tendinitis in his left hamstring.
Los Blancos, who are currently second in the La Liga table, two points behind leaders Atletico Madrid, will also definitely be without the services of Ferland Mendy, Lucas Vazquez, Dani Carvajal and Raphael Varane this weekend through injury.
Zidane cannot afford to make wholesale changes from the side that lost 2-0 to Chelsea in the second leg of their Champions League semi-final on Wednesday evening due to the importance of this match.
As a result, Toni Kroos, Casemiro, Luka Modric and Karim Benzema will all start, while there could be a spot in the final third of the field for Marco Asensio, particularly if Vinicius is not deemed fit enough to make the XI.
Eden Hazard's performance against Chelsea and conduct after the match has been heavily criticised, but the Belgium international might be handed another opportunity to prove himself here.
Real Madrid possible starting lineup: Courtois; Odriozola, Militao, Nacho, Marcelo; Modric, Casemiro, Kroos; Hazard, Benzema, Asensio