MESA, Ariz. (AP) _ Former heavyweight champion Mike Tyson appeared in court Thursday and learned he will go on trial Aug. 20 on charges of drug possession and driving under the influence of drugs.

Tyson was fresh out of a California rehabilitation facility and said very little during the five-minute proceeding.

``Yes, ma'am'' were his only words, uttered after Maricopa County Superior Court Judge Sherry Stephens asked if he agreed to the trial date, which was pushed back 30 days at his lawyers' request.

Tyson did not speak outside the courtroom, where reporters peppered him with questions and followed him to a Cadillac Escalade.

``We're very pleased with Mike's progress in treatment,'' said Richard Schonfeld, one of Tyson's lawyers. ``He's 72 days sober. We're proud of him.''

Tyson was arrested Dec. 29 in Scottsdale. A resident of the wealthy Phoenix suburb of Paradise Valley, the 40-year-old was pulled over after leaving a nightclub. An officer found bags of cocaine in his back pocket and another in a pack of cigarettes in his car, according to court records.

Tyson pleaded not guilty on Jan. 22 in Maricopa County Superior Court to felony drug possession and paraphernalia possession counts and two misdemeanour counts of driving under the influence of drugs.

County Attorney Andrew Thomas has said Tyson has run out of second chances, and prosecutors will pursue prison time. If convicted on all four charges, Tyson could be imprisoned as long as 7{ years.

Tyson's next pre-trial hearing is set for May 24, but he will be allowed to appear by telephone because his lawyers don't want to interrupt his treatment, Schonfeld said.

Stephens pushed Tyson's trial date back by a month to August because his lawyers said they hadn't seen all the state's evidence in the case.

Tyson was convicted of rape in Indiana in 1992 and pleaded no contest to misdemeanour assault charges in Maryland in 1999.

Tyson became the youngest heavyweight champion in history at 20 in 1986, when he knocked out Trevor Berbick. Four years later, he was knocked out by James (Buster) Douglas. By 1997, Tyson's career hit a low point when he bit Evander Holyfield's ear during a fight.