Joao Felix has been ruled out of Atletico Madrid's LaLiga game against Celta Vigo on Tuesday due to an ankle injury.
Portugal forward Joao Felix was substituted in the 54th minute of Atletico's 3-0 victory over Real Mallorca on Friday
Tests carried out on Sunday revealed the 20-year-old has suffered "a traumatic bone edema in the ankle", the club said in a statement on Monday.
Although it was confirmed Joao Felix will miss the trip to Balaidos to face Celta, Atleti did not provide a time frame for his recovery.
Joao Felix has struggled to live up to expectations in his first season with Atleti, who shelled out €126million to sign him from Benfica last year.
He has scored eight goals and supplied three assists in 34 appearances in all competitions.
The attacker has already missed 10 games due to two separate injuries this term and one more through suspension.