Jeschke was found guilty on seven counts of sexual misconduct, including unlawful sexual intercourse, oral copulation and sex with a foreign object. He also was found guilty of providing marijuana to a person older than 14 and for possession of marijuana.
Jeschke had faced charges of providing alcohol to minors, but was not found guilty. He also was accused of providing cocaine and ecstasy to the victim, then 16, but a hung jury issued a 7-5 vote.
Deputy attorney Joyce Dudley said Jeschke faces 10 years in prison. He will be sentenced June 24.
She said prosecutors also will press charges on three counts of witness intimidation, which came to light near the end of the trial.
Jeschke had contacted one of his former tennis players, now in college, and asked her to send threatening Facebook messages to Jeschke’s accuser. The messages were sent just before she took the stand, saying she would “be ripped apart and look like a complete idiot” if she testified against him.
Throughout the trial, many others came forward to testify, including other girls on the tennis team, girls who received private lessons from Jeschke, school administrators, and friends and parents of the girl who had the sexual encounter with Jeschke.
Last week, the girl, now 18, faced hours of questioning from Dudley and from Jeschke’s Los Angeles-based defense attorney, Lara Yeretsian. In her unemotional testimony, the girl recounted having sex with Jeschke twice in November 2007, once in his car and once at a house he was watching for a friend.
Dudley said she was satisfied with the jury’s verdict.
“I think the very clear message is that when these things are reported, they will be taken seriously,” she said, adding that each one of the girl’s allegations on sex charges was prosecuted. “That’s huge. She can go on with her life, now that he’s behind bars.”