Real Madrid, second in La Liga, announced on Wednesday that their French international striker Kylian Mbappé suffered a left thigh injury during the match against Deportivo Alavés (3-2) on Tuesday in the seventh round.
The Spanish giant wrote in a press release: "After the medical examinations carried out today on our player Kylian Mbappé by Real Madrid's medical department, he has been diagnosed with a left biceps femoris muscle injury."
Real Madrid did not specify the duration of their new star's absence, while Spanish media suggested he could be out for three weeks. Other reports mentioned that he would miss Sunday's match against Atlético Madrid.
The 25-year-old player was substituted in the 80th minute of the match and pointed to his thigh while leaving the field.
Mbappé, who joined Real Madrid from Paris Saint-Germain this year, has been performing brilliantly this season, scoring seven goals for the team in nine matches across all competitions.
The Royal Club is currently in second place in La Liga with 17 points, just one point behind Barcelona, who have played one less match and are set to face second-to-last Getafe later on Wednesday.