The Nigerian international picked up an injury in Real Sociedad's loss to Getafe on Sunday.
Super Eagles star Umar Sadiq has received the worst possible news following his injury in Real Sociedad's clash against Getafe on Sunday evening.
Sadiq, who joined Sociedad in the summer, walked off in the 38th minute after landing awkwardly following a dribble from a Getafe player.
Initially, the injury was thought to be nothing serious, but tests showed that the Nigerian international had damaged his knee and would need to undergo surgery.
The White and Blues revealed this in a statement on their social media platforms and website.
Real Sociedad's statement read: Sadiq has been diagnosed with a rupture of the anterior cruciate ligament. The player will undergo surgical treatment.
The latest development means the Super Eagles star is out for the rest of the season. It is a big blow for Sadiq, who only joined Sociedad from Almeria on deadline day.
The 25-year-old signed a six-year deal worth €20m with The White and Blues following an exceptional two years with Almeria, which saw him score 38 league goals.
Sadiq started his Sociedad career with a debut goal against Atletico Madrid, but the Nigerian will play no further part for his side this season.
His injury is also a big blow for Super Eagles coach Jose Peseiro, who is set to name his squad for the friendly match against Algeria later this month.
The Portuguese tactician is already without Victor Osimhen, while Calvin Bassey is also a doubt for the game. Sadiq's injury means he will also miss Nigeria's friendly against Portugal on November 17.