The Indians said Thursday the arthroscopic procedure will be performed by renowned orthopedist Dr. Richard Steadman in Vail. Steadman will assess the condition and stability of the cartilage beneath Sizemore's kneecap. There is a possibility Sizemore could have microfracture surgery, where tiny holes are drilled into the knee to stimulate cartilage growth.
If that happens, Sizemore would be done for the season.
"I just hope that when Dr. Steadman goes in, it's not so bad and Grady can have the simplest procedure and be back as soon as possible, for his own good," manager Manny Acta said before the Indians closed a three-game road trip in Detroit. "Then he can play for us whenever he's ready."
At the minimum, Sizemore is expected to miss at least six weeks.
Sizemore initially bruised his knee sliding into a base in April. He went on the disabled list May 16.
Sizemore missed the final month last season after having surgery on his abdomen and left elbow, injuries that hounded him throughout the worst year of his career.
Before this rash of injuries, which limited Sizemore to 106 games last season, he played in at least 157 games in each of the previous four seasons. He played in 382 consecutive games from 2005 to 2008.