WALTHAM — Kendrick Perkins, the player primarily responsible for guarding Orlando’s Dwight Howard, was held out of practice on Saturday with a sore right knee. Perkins wore wraps on both knees and kept ice on his right one until the end of practice.

“He tried to go early and it bothered him a lot.” Rivers said. “He wanted to go I said, ‘I don’t need you tonight. You’re not going to help me today in practice. I need you tomorrow.’”

Following practice in Waltham, the Celtics left Saturday for Orlando and Sunday afternoon’s Game 1 of the Eastern Conference finals. Tipoff is set for 3:30 p.m. ET.