Zhou collided with Sharks forward Luis Scola late in the first quarter and was taken off the court in a wheelchair after trainers and staff helped him up.
The 7-foot-2 Zhou, who had played just four minutes before suffering the injury, was making his first preseason appearance.
When asked how serious the injury to Qi was, coach Mike D'Antoni said: "I think it's just a sprain. That's what they're saying. Obviously he'll get an MRI and hopefully that stays the same news. But just a sprain."
A 2016 second-round draft pick out of the Chinese Basketball Association, Zhou made his NBA debut just less than a year ago, on Oct. 21, 2017, with the Rockets.
Zhou, 22, played in 18 games last season, averaging 6.9 minutes in those contests.