Mbappe sustained a hyperextension of the posterior capsule of his left knee during France’s 1-0 Nations League victory over Turkey on Friday.
The French forward scored the only goal of the match 10 minutes into the second half, curling a shot into the bottom-left corner from inside the box before leaving the pitch shortly afterwards.
‘Following tests carried out today by Real Madrid’s medical department on our player Kylian Mbappe, he has been diagnosed with a hyperextension of the posterior capsule of his left knee,’ the Spanish club said in a statement.
The injury rules the France captain out of the remainder of the national team’s Nations League fixtures over the next 10 days.
New France coach Zinedine Zidane said the team would not take risks with Mbappe’s fitness, with France travelling to Belgium on Monday before facing Italy and Belgium at the Stade de France on October 2 and 5.
The timing of the injury has raised concerns at Real Madrid, with the club preparing to resume La Liga action after the international break.
Madrid’s first fixture back is against Villarreal on October 10, although Mbappe’s return for that game remains uncertain.
Spanish newspaper AS reported that the forward could be fit in time for Real Madrid’s El Clasico against Barcelona on October 25.
Mbappe’s absence would be a significant setback for Real Madrid, given his importance to the club’s attack and his role as France captain.
For now, the extent of the injury and his recovery timeline will determine whether Real Madrid must cope without their leading forward for several weeks or potentially longer.