Real Madrid endured a nightmare trip to the Basque Country as Eibar ran out 3-0 winners to condemn Santiago Solari to his first defeat as permanent Los Blancos coach.
Solari's impressive start as Real's caretaker manager persuaded Florentino Perez to hand the 42-year-old an 18-month deal to coach the Champions League holders.
Solari won his first four games in charge before the international break, but Real's return to domestic action ended in a heavy defeat as Eibar fully deserved their healthy three-goal margin over the Spanish giants.
Gonzalo Escalante's 16th-minute goal was eventually awarded following a lengthy VAR review to send Eibar into the break ahead, and Sergi Enrich took advantage of more poor Real defending after the break.
Enrich put Eibar two goals to the good 52 minutes in, and Kike put the hosts in dreamland with a third just five minutes later.
Solari substituted Luka Modric soon after, but it made no difference as Eibar looked the only side likely to add more goals as Thibaut Courtois was forced into a number of saves to prevent a rout.
The result is particularly damaging for Real given champions Barcelona face potential title rivals Atletico Madrid later on Saturday.
