Yao suffered a fracture on the front of his right anteria tibia, a weight-bearing spot where the knee connects to the legbone, in the first quarter of Saturday's loss to the Los Angeles Clippers.

The injury came when Clippers forward Tim Thomas drove to the basket and Yao and teammate Chuck Hayes moved to block the shot. Thomas ran into Hayes and both hit Yao, sending him to the floor in pain.

The star Chinese center will be sidelined for at least six weeks and could miss more time if surgery is required.

The Rockets games with Yao are always the eye-catching program for China's broadcasters, but Yao-less Rockets will lose a lion's share of live viewers in China and even worldwide.

A sports producer with CCTV, China's national broadcaster, voiced the broadcaster's concerns of a plummet in enthusiasm to watch Rockets' matches.

"It is unknown now that how low the TV viewing rate will drop to, but last season had already proved Yao is the backbone of viewing rate," said the producer who preferred not to be named.

According to the producer, CCTV is quite likely to rearrange its broadcasting scheme as of January 2007, increasing the exposure of other teams' games.

The TV viewing rate is not the only victim from Yao's sideline. The NBA lottery in China also looks set to suffer a setback as Rockets' matches account for up to half of the total in bidding. Yao's absence will defuse the fervor of lottery buyers.

Yao and Tracy McGrady's injury drained Rockets' seating capacity a lot as the tickets for Friday's game against Atlanta Hawks faltered to only ten dollars.

Yao, 26, was in the midst of his finest NBA season, averaging 26.8 points and 9.7 rebounds a game.

When star guard Tracy McGrady was sidelined by back spasms seven games ago, Yao stood in and became an aggressive, dominant leader.

But now he needs a strong rehabilitation effort to regain his superstar form.

Yao will miss at least 18 games and return in early February, possibly in time to play in the NBA All-Star Game. Voters have elected him a starter in his first four NBA seasons.

Yao missed 21 games in a row last season with a big toe injury and four more with a broken left foot. McGrady missed much of the season as well and the Rockets struggled to 34-48 win-lose record.

The same fate could befall Houston again.