Houston Rockets' all-star center Yao Ming's basketball career has been cast in doubt after reports revealed yesterday his injury is worsening.

The injury may force him out of action for the next NBA season or possibly end his career.

Rockets team physician Tom Clanton told the Houston Chronicle that the Chinese superstar's broken left foot could be a "career-threatening" injury.

"Yao is not experiencing any pain in his left foot. However, the results from the CT and bone scans we performed over the past two days indicate that the hairline fracture has not responded to the degree that we expected," Clanton said.

"We will review a variety of treatment options before proceeding.

"At this point, the injury has the potential for him missing the next season and could be career-threatening."

No other Rockets official was available for comment last night.

Chinese fans were shocked at the news yesterday and some blamed Rockets' tactics in using the giant center.

But reports of the injury ending the all-star center’s NBA career were quickly dismissed by his agent.

"I heard some reports saying Yao's career might be over due to the worsening injury," said Zhang Mingji, who goes by the name of Eric Zhang in the United States. "I don't think it's the right time to say that.

"I can assure you the (Houston) Rockets have never come to a conclusion concerning Yao's career."

Zhang, however, did admit that the previous treatment on the superstar's broken left foot did not work as hoped.

The China Basketball Administrative Center said it's been informed of the news. But a chief official assumed it would not rule Yao out of the World Championships next year.