BEIJING (AP) _ A neck injury to champion John Ruiz has forced the postponement of his WBA heavyweight title defense against Evander Holyfield, promoter Don King announced Friday.

No new date has been set for the fight that was to have taken place Aug. 5 in Beijing.

Ruiz first complained of a stiff neck Tuesday evening and his condition had worsened by Wednesday morning, his manager, Norman Stone said.

``He cannot fight at this time,'' Doctor Qu Minyang said.

The bout would have been China's first world heavyweight title fight.

``Injuries are a part of boxing,'' Holyfield said. ``John was very gracious when I suffered an injury before our first fight was postponed. I know he came to Beijing to fight and when he's ready, so am I.''

Ruiz became champion by outpointing Holyfield on March 3.