Eibar, playing at home, equalized off a corner kick in the 50th minute and looked like it might steal a point from the reigning league champs.
Real Madrid won the match 2-1.
Real´s win in La Liga moves them to within four points of second-placed Atletico Madrid, who play at home to Celta Vigo on Sunday.
Real Madrid are on the surge for an unprecedented third Champions League crown in three years, having once again advanced to the quarter-finals of the competition.
Tiny Eibar are in contention for a European place next season and made the better start to the game, with Zidane admitting his side struggled in the opening stages.
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It's the latest engagement of a tour of Britain which the couple are carrying out ahead of their May 19th wedding. Meghan and Harry are set to marry in May this year in an intimate ceremony in the grounds of Windsor Castle.
Zidane added: 'He's from another galaxy.
Isco saw a 23rd minute shot blocked inside the Eibar box, but after Joan Jordan saw his header from a Pedro Leon free-kick fly just wide of the target, Real found themselves in the lead, very much against the run of play.
Ronaldo put the European champions ahead in the 34th minute following a attractive pass from Luka Modric.
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The difference is that SC wasn't part of the SEC until 1991-92 while Texas A&M and Missouri just joined the league in 2012-13. This Michigan team has been coach John Beilein's best on the defensive side since he took over in Ann Arbor in 2007.
In front, Real improved but five minutes into the second half and Eibar were level.
Ronaldo should have restored the advantage but failed to convert an excellent Bale cross and from the resulting corner, Bale flashed a glancing header just wide of the post.
Ronaldo subsequently punished that miss, meeting Dani Carvajal's right-wing cross with a powerful header that gave Dmitrovic no chance and sent Madrid back to the capital victorious.
Real Madrid's Cristiano Ronaldo celebrates his second goal beside Lucas Vazquez after scoring during the Spanish La Liga soccer match between Real Madrid and SD Eibar at Ipurua stadium, in Eibar, northern Spain, Saturday, March 10, 2018.
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While rumors have swirled suggesting Porter Jr. could play any day after recovering from back surgery , he hasn't taken the floor. Fox 2 Sports reporter Charlie Marlow was at Scottrade Center and had the post game report from the disappointing Mizzou loss.