BARCELONA, Sept 23, 2024 (BSS/AFP) - Robert Lewandowski and Raphinha struck twice each as La Liga leaders Barcelona romped to a 5-1 win at Villarreal on Sunday but were left fearing a "huge" knee injury to goalkeeper Marc-Andre ter Stegen.

Atletico Madrid, fourth, were held to a 1-1 draw at city rivals Rayo Vallecano as Conor Gallagher netted his second goal for the Rojiblancos.

Barcelona's sixth league triumph in six games was marred by Ter Stegen being taken off on a stretcher after falling awkwardly having collected a cross, with early reports suggesting he could miss the rest of the season.

"I think it will be a huge injury, when he laid down on the field... you can see it directly," Barcelona coach Hansi Flick told DAZN.

Lewandowski netted Barcelona's first two goals and later missed a penalty in a thoroughly entertaining battle on Spain's east coast at Villarreal's Estadio de la Ceramica.

Ayoze Perez pulled his team back into the game shortly before half-time and the previously unbeaten hosts had two goals disallowed, with Pablo Torre and Raphinha's strikes cementing Barcelona's victory.

After second-placed Real Madrid thrashed Espanyol 4-1 on Saturday the Catalans were able to restore a four-point lead on the champions.

"It's very important for us that we played a game away from home, we scored five goals and in the end we have three points," said Lewandowski.

"In the end it doesn't matter how, as long as we win that's perfect."

Flick gave Eric Garcia another start in defensive midfield despite his early red card against Monaco in the Champions League midweek defeat.

The German coach also started reserve team players Gerard Martin and Sergi Dominguez, as well as playmaker Torre in place of the injured Dani Olmo.

Teenage star Lamine Yamal hit the post early on before Lewandowski slotted home in the 20th minute after Torre slipped him in.

Villarreal goalkeeper Diego Conde did well to keep out a bundled effort from the Polish striker but Lewandowski pounced after 35 minutes for his second.

Conde saved Garcia's header well but the former Bayern Munich hitman converted the rebound with an acrobatic finish from close range.

It was his sixth La Liga goal of the season, taking him two clear of Real Madrid's Kylian Mbappe in Spain's golden boot race.

- 'Special person' -

Villarreal were frequently threatening on the counter and Perez gave them a lifeline after the electric Nicolas Pepe set him up.

Ter Stegen thwarted Pepe with a sensational save one-on-one before half-time but the German Barca captain was soon stricken as he fell badly after catching a corner before the break and was replaced by Inaki Pena.

Pepe finished brilliantly early in the second half but his effort was disallowed for a marginal offside call, and Yeremy Pino hit the bar with a header as Marcelino Garcia Toral's side drove Barcelona back.

Torre extended Barca's lead with a deflected strike from the edge of the box, a killer blow given Villarreal's momentum.

Lewandowski hit the post from the spot after Eric Bailly scythed down Yamal and Villarreal's Thierno Barry had a goal ruled out for offside.

Raphinha ended any hopes of a home comeback, first with a deflected shot and then finishing after a superb Yamal pass left him with just Conde to beat.

"(Ter Stegen) is a very special and important person in the dressing room, this victory is 100 percent for him," Raphinha told DAZN.

Real Madrid goalkeeper Thibaut Courtois wrote Ter Stegen a message on social media platform X.

"It hurt me a lot to see you leave the pitch like that," wrote the Belgian stopper.

"I hope you can recover soon and we see you again in goal."

In a Madrid derby clash Diego Simeone's unbeaten Atletico could not find a way past Rayo Vallecano.

Rayo's Isi Palazon slammed home from close range after 35 minutes and the goal was eventually given after initially being ruled offside.

However Gallagher finished neatly from the edge of the box early in the second half when Alexander Sorloth fed the England international.

"(At half-time Simeone) told us we all had to run, these days anyone who is not running here cannot play," Atletico captain Koke told Movistar.

"We had chances to get the winner but it wasn't to be."

Athletic Bilbao overtook Atletico to move into third with a 3-1 win against Celta Vigo.