The Brazilian International forward was hurt in the 1-0 win against Celta Vigo on Friday.
Real Madrid forward Vinicius Jr. facing a spell on the sidelines after damaging his hamstring.
Vinicius was injured after 18 minutes of Real’s 1-0 LaLiga win at Celta Vigo on Friday.
“After the tests done on our player Vini. Jr, the medical service of Real Madrid (he) has been diagnosed with an injury to the right biceps femoris,” the club said in a statement.
“His progress will be monitored.
The 23-year-old Brazilian will miss Real’s last game before the international break at home to Getafe.
There are also concerns that Vinicius could miss Real’s league games against Real Sociedad and city rivals Atletico after the international break, as well as the start of their Champions League campaign next month.