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.