Real Mallorca forgot their Primera Liga woes to beat Almeria 3-1 in a Copa del Rey last-16 first leg tie on Thursday.
The 2003 Cup winners, who have slipped to second from bottom in the league after seven games without a win, were given an eighth-minute lead by Alhassane Keita.
Almeria equalised almost immediately and visiting goalkeeper Esteban Suarez also saved a penalty before further strikes from Cleber Santana and Fernando Varela completed a convincing home victory.
In icy Pamplona, bottom club Osasuna were held to a 1-1 draw by northern rivals Athletic Bilbao.
Walter Pandiani looked to have scrambled Osasuna a win when he scored nine minutes from the end but Fernando Llorente levelled in stoppage time.
Earlier in the week, Barcelona won 3-1 at Atletico Madrid, Sevilla beat Deportivo Coruna 2-1 and holders Valencia drew 1-1 at Racing Santander.
Third tier Poli Ejido registered the surprise result of the first legs, beating Espanyol 3-2 on Wednesday.
The return matches are next week.