Updated

The Cleveland Cavaliers announced center Anderson Varejao will undergo knee surgery on Thursday and is expected to be sidelined 6-to-8 weeks.

Varejao hasn't played since suffering a right knee contusion against the Toronto Raptors on Dec. 18.

The team issued a statement explaining Varejao's injury.

"Diagnosis was a right knee contusion, specifically to the vastus medialis which connects to the medial (inner) border of the patella. As Varejao's treatment and recovery process continued, an MRI revealed the contused area included a small longitudinal split in the vastus medialis. Despite continued, gradual recovery of the contusion, symptoms also continued in the specific area of the split. Another MRI revealed an increase in the split and symptoms persisted. Dynamic ultrasound imaging also revealed tissue from underneath the split was herniating and pinching with knee flexion."

Varejao has averaged 14.1 points and 14.4 rebounds in 25 games this season.