The France forward limped off in the first half of Friday’s 1-0 win over Saint-Etienne after a dreadful tackle that resulted in a red card for opposing captain Loic Perrin.
PSG said Tuesday medical imaging had confirmed the initial test results of a sprained right ankle, with Mbappe also sustaining ligament damage.
The club indicated the expected timeline for his return was “around three weeks”, meaning he will miss Friday’s French League Cup final against Lyon.
The diagnosis also leaves Mbappe a huge doubt for PSG’s resumption of their Champions League campaign, although the 21-year-old could be fit to return for the semi-finals if Thomas Tuchel’s side advance.
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