Yao said his knee was "close" to being healthy enough to play Sunday night against the Detroit Pistons and hoped to be back in the lineup Monday night on the road against the New York Knicks.
"It's another 24 hours," he said.
"X-ray pictures show everything is fine, no cracks. I think I will be fine."
Houston coach Rick Adelman said he has "no idea" when Yao will play again, saying he's day to day.
"He was hoping to play, but it's still a little bit sore and it's bothering him," Adelman said. "So, there's no reason to push him at this point.
"We'll see how he feels [Monday]."
The 7-foot-6 center left Friday night's game at Indianapolis because of a sore right knee and did not play after halftime.
McGrady has missed 16 games with a sore left knee, which underwent surgery in May, and Artest has been out 13 games with an injured right ankle.
Yao is averaging 19.6 points, 9½ rebounds and 1.7 blocks, missing only one game previous to Sunday night's matchup.
"I try to push it and [my foot] push back," Yao joked. "They want me to play the whole season and don't want me to rush."