Saracens and England lock Nick Isiekwe will have surgery this week which will keep him out for "several months".
The 24-year-old's club said it had been "recommended to carry out a procedure" after discussion with a consultant.
Isiekwe, who came through the Saracens academy, made his first-team debut aged 18 before winning his first England cap the following year.
He has already featured more than 100 times for his boyhood club, and has eight caps for Eddie Jones' side.
Saracens said they will update further on Isiekwe's return during his rehabilitation.