Barcelona's Ousmane Dembele celebrates scoring a goal during the match against Atletico Madrid | Photo: AFP
Madrid: Ousmane Dembele's strike sent Barcelona three points clear at the top of La Liga with a tense 1-0 win over Atletico Madrid on Sunday.
Earlier David Silva produced a masterclass to help third place Real Sociedad beat Almeria 2-0, while Real Betis moved fourth with an entertaining 2-1 win at Rayo Vallecano.
Struggling Sevilla earned a crucial 2-1 win over Getafe to climb out of the relegation zone on goal difference.
Capitalising on champions Real Madrid's defeat by Villarreal, Barcelona set out to make a statement victory over Atletico at the Metropolitano.
Shorn of suspended top scorer Robert Lewandowski, Xavi selected Ansu Fati up front in his place, but it was Dembele who made the difference, finishing a slick move in the 22nd minute.
Atletico ramped up the pressure, with the superb Ronald Araujo clearing off the line from Antoine Griezmann at the death, but Diego Simeone's side could not find an equaliser.
Both teams finished with 10 men after Ferran Torres and Stefan Savic were sent off for brawling with each other on the floor as tempers soured.
"It's a win, but it's not just three points. It gives us morale and confidence for what's left of the league," Xavi told reporters.
"We are capable of winning at place as tough as this, suffering, being a family.
"We knew how to suffer and we take three golden points. It's a real statement that we are candidates to win this league."
Barcelona have conceded just six goals in their first 16 La Liga matches but Griezmann twice came close to finding the equaliser Atletico craved.
The Catalans only mustered two shots on target and Atletico goalkeeper Jan Oblak said his side deserved more.
"We had a good game, apart from the first 25 minutes," Oblak told DAZN.
"We pressed well, we had chances, but lacked a bit of luck to score."
"We started badly, the first 25 minutes we had little confidence, and later we woke up, but at 1-0 down it's already harder."
Defeat means Atletico languish in fifth, 14 points behind leaders Barcelona.
"It's not a worrying situation but it is one that we have to deal with," Simeone told reporters.
"The reality is that we lost. It's true the team had the merit to take away another result, that didn't happen because we didn't put it away. What happens in the boxes is crucial."
Youngster Fati had an early effort brilliantly blocked by the sprawling Jose Gimenez, as Barcelona dominated the opening exchanges.
Xavi said on Saturday Atletico barely have any gaps in their defence but Pedri uncovered one to create the opening goal.
The midfielder capitalised on space in front of the box, before feeding Gavi, who teed up Dembele to clinically slot home.
Marcos Llorente had Atletico's first decent opportunity after half an hour when Griezmann scooped a ball delicately over the defence to set him in, but Araujo deflected his effort wide.
The hosts wrestled back control and Marc-Andre ter Stegen made a superb save at full stretch to deny the pink-haired Griezmann, becoming increasingly influential against his former side.
Atletico began the second half in determined fashion, pushing Barca deeper and deeper.
Only Griezmann's compatriot Dembele offered the leaders an outlet on the break and he had a drive deflected into the side-netting.
Xavi brought on Franck Kessie for De Jong and it helped steady the ship, with Barcelona managing some stretches of possession which frustrated the home fans.
Red cards for Torres and Savic reignited the game in stoppage time and Griezmann might have snatched a point but for Araujo's crucial clearance on the line.
Real Sociedad's veteran Spanish playmaker Silva, 37, capitalised on defensive confusion in Almeria's box to nip in and fire home the opener just after half-time.
Alexander Sorloth drilled home his sixth league goal of the season five minutes later to extend La Real's lead.
Without the suspended Brais Mendez, Imanol Alguacil's side were not at their best but still managed to inflict promoted side Almeria's first home defeat since September, leaving them 14th.
The victory leaves Alguacil's side in high spirits ahead of next weekend's Basque derby clash with Athletic Bilbao.