Antoine Griezmann scored three goals in a 3-0 La Liga victory over Getafe on Wednesday to secure Atletico Madrid's Champions League qualification.
Diego Simeone's side are now assured that they would finish in the top four on the league table and qualify for Europe's elite tournament for the 12th consecutive season.
The Rojiblancos, led by France international Griezmann, romped to victory in the Madrid suburbs at Getafe's Coliseum Alfonso Perez.
Atletico, 4th on the table, trailed Girona by two points but now leads Athletic Bilbao by 11 after the Basque team lost 2-1 to struggling Celta Vigo.
Despite a promising start and becoming the first team in Spain to defeat new champions Real Madrid this season, Atletico's season began to crumble.
Athletic ousted them in the Copa del Rey semi-finals and Borussia Dortmund knocked them out in the Champions League quarters.
Atletico knew that a victory would secure their return to the competition the following season, and the great Griezmann did not give Getafe, who finished 10th, a chance.
The 33-year-old forward had only scored twice in his previous 13 La Liga games, prompting questions about his form, but he put them to rest with his second treble of the season.
Atletico's all-time record goalscorer opened the scoring in the 27th minute, running on to Rodrigo De Paul's scooped ball and beating Getafe stopper David Soria with a low attempt.
Griezmann scored his second goal before halftime from Angel Correa's low ball across the box, which was awarded following a VAR review after being ruled offside.
