O'Neal did not travel with the Cavaliers for their game at the Washington Wizards on Wednesday night, the third consecutive time he sat out.
Cleveland coach Mike Brown said O'Neal also will be out Friday at Indiana, and the center also might be sidelined for Saturday's home game against Philadelphia.
"It's early in the year. We all have a better comfort level than what we had in Game 1, Game 2, Game 3. And so in my opinion, it's an opportune time to let him get some rest and let him get his body back," Brown said.
Asked if it's that he doesn't want O'Neal to play every game, Brown replied: "I'm not thinking of, 'He's got to play 'X' amount of games.' Just like in practice, I'm not thinking, 'He's got to practice 75 percent of the time."
Then, pointing to his gut, Brown continued: "It's just right here, and if I feel it, I sit him down. If I don't, then I won't. If he feels it, hopefully he'll communicate it with me, and same with our trainers. We'll just kind of go from there. But really it's not anything I'm doing that's scientific or with a formula to it. I'm not that smart."
O'Neal is playing about 24 minutes per game this season, averaging 11.3 points and 6.8 rebounds.
Anderson Varejao has a bruised hip and also was inactive against Washington.
"If tonight was a playoff game, he would play," Brown said.
The Cavaliers entered Wednesday on a five-game winning streak.