The six-foot six, three-times All-Star was injured in Sunday's 91-88 win against the Los Angeles Lakers and needs surgery to repair a torn meniscus in his right knee.
"This was not an easy decision to make," the 25-year-old said in a statement released by Portland. "If we're fortunate enough to advance in the playoffs, having the surgery now gives me the best opportunity to help our team."
The sixth-seeded Trail Blazers face the third-seeded Phoenix Suns in the best-of-seven series starting on Sunday in Phoenix.
(Writing by Mark Lamport-Stokes; Editing by Ian Ransom)