Manchester City produced a stunning display to beat Manchester United 4-1 and restore a six-point advantage over Liverpool at the top of the Premier League, while Barcelona rejoined La Liga's top four after needing a late penalty to beat Elche 2-1 on Sunday.

Kevin De Bruyne and Riyad Mahrez scored two goals each as Manchester City had a convincing 4-1 derby victory over Manchester United at the Etihad Stadium on Sunday.

United had put up a decent fight in the first half, going in 2-1 down at the break, but City's quality showed after the interval with Ralf Rangnick's side looking increasingly demoralized.

Belgian De Bruyne was outstanding, running the game from central midfield and then presenting himself as a threat in the box.

United were without Cristiano Ronaldo and Edinson Cavani through injuries and surprisingly Rangnick opted to play Paul Pogba and Bruno Fernandes in forward positions.

"It was excellent from the first minute. We played really well and had to be patient in the first step," said City's manager Pep Guardiola.

"Football is emotions. It's tactics, definitely, but it's also emotions. Without the ball, we are a team with desire and passion to regain the ball from the first minute to the 90th," he added.

Barcelona fought back to earn a 2-1 win in a frantically entertaining match at Elche as a late penalty from Memphis Depay ensured they continued their revival after a difficult start to the season.

Having fallen as low as ninth back in November, when former coach Ronald Koeman was fired, Xavi Hernandez's revitalized Barca have climbed into La Liga's top three with 48 points, leapfrogging Betis in third place.

Mid-table Elche opened the scoring right before halftime when Pedri tried to clear the ball but gifted a perfect assist to Fidel Chavez, who out-ran Dani Alves and scored with an angled shot just inside the right post.

Ferran Torres scored the equalizer in the 61st minute after great play from Ousmane Dembele down the right flank.

The next 20 minutes were frantic, with both teams creating scoring opportunities only to be denied by goalkeepers Marc-Andre ter Stegen and Edgar Badia.

Barca's winner arrived after the video assistant referee spotted a handball from an Elche defender inside the area in the 84th minute and Depay rifled his penalty into the top left corner.

The VAR was put to work twice more after that, as Elche were controversially denied two penalties following handball appeals against Barca players.

"Handballs inside the box can always be discussed," Ter Stegen told reporters.

"Players can't take their arms off their bodies inside the area. I think the referee made the right decisions."