SANTA ROSA -- A former Sonoma Valley youth soccer coach pleaded not guilty Thursday to an amended complaint charging him with 31 counts of committing sexual acts with an underage girl on his traveling team.

Gregory Vance Tatton, 43, was scheduled for a preliminary hearing. He was initially was charged with five counts of committing lewd and lascivious acts with a girl under age 17 and five counts of oral copulation with a girl under age 18.

The hearing was postponed because defense attorney Ethan Balou said he has not received documents that might serve as evidence from the prosecution on the amended complaint.

Balou also has subpoenaed medical records from Kaiser Permanente in Petaluma and records from three schools the alleged victim attended. The preliminary hearing is now set for Aug. 13.

The amended complaint alleges Tatton committed seven lewd and lascivious acts with a minor age 14 or 15, and further includes 18 charges of sex with a minor three or more years younger, and six charges of oral copulation with a person under age 18.

Tatton, a Sonoma Valley Youth Soccer Association coach, was dismissed after his November 2007 arrest for having false registration tags on his vehicle, but there were rumors about his ongoing sexual relationship with at least one of the girl players, Sonoma County Sheriff's Sgt. Dave Thompson said. The sheriff's department began investigating the allegations at that time.

The alleged victim was on the soccer association's traveling team for girls under age 17, which played as far north as Redding and as far south as San Diego, Thompson said.

Sheriff's detectives arrested Tatton April 3 at a home in West Hollywood, Thompson said. Tatton was staying with friends in the Los Angeles area, Thompson said.

He is free after posting $150,000 bail.