Barcelona and Real Madrid both face difficult starts to 2017 after drawing Athletic Bilbao and Sevilla respectively in the Copa del Rey on Friday.
Barca and Madrid eased into the round of 16 with huge wins against lower league opposition in Hercules and Cultural Leon, but they face tougher tests in the next round against two teams doing well in La Liga.
Real Madrid have been drawn against 2016 runners-up Sevilla in the last 16 of the Copa del Rey.
Sevilla have made an impressive start under Jorge Sampaoli.
Holders Barcelona take on Athletic Bilbao, the side they beat in the final of the competition in 2015.
Atletico Madrid will meet Las Palmas, Real Sociedad play Villarreal and struggling Valencia take on Celta Vigo in some of the other ties.
The first legs will be played on or close to Jan. 4 and the second legs will be played the following week on or around Jan. 11.
Copa del Rey round of 16 draw:
Las Palmas vs. Atletico Madrid
Alcorcon vs. Cordoba
Athletic Bilbao vs. Barcelona
Real Madrid vs. Sevilla
Real Sociedad vs. Villarreal
Deportivo La Coruna vs. Alaves
Valencia vs. Celta Vigo
Osasuna vs. Eibar