Atletico Madrid pulled off their first La Liga win over Barcelona in more than a decade as Yannick Carrasco capitalised on a blunder from goalkeeper Marc-Andre ter Stegen to secure a 1-0 victory at an empty Wanda Metropolitano.
Belgian winger Carrasco broke the deadlock at the end of the first half, pulling off a classy backheel to knock the ball through the legs of Ter Stegen and keep his composure in front of goal after the German had charged out of his area.
Lionel Messi had won the fixture last season with a late solo goal but the Barca captain had a match to forget this time, creating very little danger and appearing hesitant in front of goal.
Barca's former Atletico forward Antoine Griezmann missed the target in each half while defender Clement Lenglet had their best chance when, unmarked, he could only send his header straight into the arms of keeper Jan Oblak.
The win moved Atletico up to second in the standings, level on 20 points with leaders Real Sociedad, while Barca are down in 10th place with 11 points after a third defeat in eight league games under Ronald Koeman.
"A team like Barca cannot afford to concede a goal like that," said the Dutchman.
"It was our fault, it's not good and we can't let something like that happen again."
The Catalans' pain was compounded by the sight of defender Gerard Pique limping off the pitch in tears after a challenge from Angel Correa.
A club medical report eased initial fears that Pique had torn knee ligaments and said he had strained them, meaning he will be out for about six weeks.
Barca's players had come out for the game wearing T-shirts in tribute to their teenage striking sensation Ansu Fati who recently underwent knee surgery and they were also missing midfield anchor Sergio Busquets, a veteran of the fixture.
Atletico were without joint-top scorer Luis Suarez, who was deprived of a reunion with his former side after testing positive for Covid-19, while midfielders Hector Herrera and Lucas Torreira were also unavailable but they well deserved their victory.
Marcos Llorente nearly gave Atletico an early lead when his shot crashed off the bar, while it took a brilliant save from Ter Stegen to keep out a vicious distance strike from Saul Niguez.
While Barca had their chances to level, Atletico comfortably saw out the victory and coach Diego Simeone punched the air when the whistle came to signal his first league victory over Barca since he took charge of Atletico in 2011.
"It was our turn to win today but it won't change our objectives," said the coach.
"We knew exactly how we needed to play and that we would have to work as hard in attack as in defence."