Atletico Madrid boss Diego Simeone admitted that his side struggled in the first half of their 3-0 defeat to Real Sociedad on Thursday.
Willian Jose opened the scoring at the Anoeta Stadium on 27 minutes, while Juanmi bagged two late goals, in the 80th and 92nd minutes.
Speaking after the game, Simeone referenced losses against Villarreal and Real Madrid in recent weeks.
He told the club's official website: "Today, we played poorly in the first half and in the second half we improved at first, but didn't have the regularity to find the equalizer."
He continued: "The match against Villarreal was much more even and against Madrid as well. The first half in Lisbon was poor, but the second was good.
"We have to congratulate Real Sociedad because they played a great match and won fairly."
Midfielder Thomas Partey added: "They played well and took advantage of their chances. We have to pick ourselves up and keep fighting."
Second-placed Atletico ended the evening on 71 points, 12 points behind leaders Barcelona and three clear of Real Madrid.
They next play Real Betis at home in the league before facing Arsenal away in the Europa League semi-finals.