Oct 01, 2009 7:22 AM EST

Celtics forward Bill Walker was sent back to Boston on Wednesday to have an MRI on his surgically repaired right knee.

Walker has already had two major knee surgeries in his young career.

"His knee has been bothering him," coach Doc Rivers told the Boston Herald. "Yesterday (during) practice he said it was really bothering him, but he said he's felt it for two weeks. Let's hope it's not too bad."

Via Boston Herald