The left-back picked up an injury during the second half of their midweek derby clash against Atletico Madrid at the Metropolitano.

A problem with the biceps femoris in his left leg means he'll be out of action for at least 20 days, casting doubt over his availability for the Champions League quarter-final first leg against Arsenal on April 8 at the Emirates.

Mendy had cemented his place as Carlo Ancelotti's go-to left-back in recent Champions League knockout ties. The Italian boss had relied heavily on his defensive nous to stifle the likes of Manchester City and Atletico Madrid.

But a clumsy moment while playing a backpass to Thibaut Courtois changed everything, with Mendy instantly aware of the damage. Ancelotti turned to Fran García, who stepped up admirably for the remainder of regular time and extra time, putting in a solid shift.

Looking ahead, if Mendy recovers on the quicker side of the estimate, he could be back, just about, for that crucial Arsenal clash on April 8. There's even a slim chance he might return for the La Liga fixture against Valencia beforehand. However, should the worst-case scenario play out with a full four-week absence, he'd be racing against time to feature in the second leg against the Gunners at the Bernabeu on April 16.

Adding a twist to the tale, Wednesday's derby marked Ferland Mendy's 200th appearance in a Real Madrid shirt. The Frenchman, who lasted 83 minutes before limping off, has racked up this milestone in his sixth season with the club, during which he's lifted 13 trophies.

Reflecting on his journey, Mendy first pulled on the famous white jersey on September 1, 2019, in an away draw against Villarreal. Since then, he's notched 136 wins, with his 200 games breaking down as 128 in La Liga, 53 in the Champions League, six in the Copa del Rey, 11 in the Spanish Super Cup, and two in the European Super Cup.

Ancelotti has said of Mendy's importance: "He's a rock at the back, his ability to shut down attacks is vital for us."

But with the 29-year-old now facing a spell on the sidelines, Real Madrid will need to adapt quickly as they eye a deep run in Europe.

Ferland Mendy's misfortune rocks Real Madrid's Champions League plans