Chinese basketball club Shanxi has been sanctioned for Sunday's fan disturbances which involved Beijing's former NBA star Stephon Marbury.

The Chinese Basketball Association (CBA) on Tuesday fined Shanxi club and its venue 30,000 RMB (about 4,740 U.S.dollars) apiece for "poor organization" of the fourth game of the CBA league semifinal series.

The CBA also postponed the deciding fifth game from Wednesday to Sunday, giving both teams time to make "internal rectifications".

No sanction was made against Marbury, who was accused of beating up a fan during the post-match brawl. A CBA official told Xinhua that the league should not intervene in the case.

"It's the police's job," said Bai Xilin, CBA's sports director.

Marbury, who scored 25 points for Beijing as Shanxi claimed a 102-100 narrow win to tie the best-of-five series at 2-2, was accused of hitting a Shanxi supporter just after the bad-tempered game ended on Sunday.

During the game, Marbury exchanged words with Shanxi's Ma Kan after a collision, which triggered an outburst of the home crowd, who threw bottles onto the court, forcing a 10-minute pause of the game.

More boos were made by local fans as a foul by Randolph Morris on Marcus Williams during a lay-up in the final two minutes remained uncalled.

A large group of fans then trapped the Ducks' bus after the game and attacked the vehicle for more than an hour in the parking lot, while a Shanxi fan named Cao Lei later accused Marbury of hitting him with a bottle and kicked him after he fell.

Marbury told Beijing Television that he didn't hit anyone and the one who accused him of assault "must have a wild imagination".

"I would never kick or punch a fan," said Marbury on Weibo, China's equivalent of Twitter. "That's not my character."

Shanxi police made it public a report on Monday to back Cao's accusation, but the New York native was defended by his boss and teammates of the Beijing Ducks.

"None of my players and coaches saw Marbury hit someone when we exited the stadium," Beijing club's deputy general manager Yuan Chao told Xinhua on Monday night.

"Surrounded by two guards, his translator and trainers, he didn't have time or space to throw a punch, not to mention kick someone."

The 35-year-old Marbury, who played 13 seasons in the NBA with Minnesota, New Jersey, Phoenix, New York and Boston, has been regarded as a hero after leading Beijing to the CBA semifinals in style in his first season with the Ducks.