Mark Philippoussis' father Nick to spend another night in US prison

The father of former Australian tennis star Mark Philippoussis looks set to spend at least another night inside San Diego's tough Central Jail.

Nick Philippoussis, 68, was expected to apply for bail in court in Vista, California, on Wednesday after his arrest on multiple child molestation counts.

Philippoussis lives and works as a tennis coach in the San Diego area and his two alleged victims are aged under 14 and former tennis students, according to San Diego sheriffs.

One count, sexual intercourse or sodomy, does relate to a child aged 10 years or younger.

Nick Philippoussis, 68, was expected to be arraigned and apply for bail in court in Vista, California, on Wednesday after his arrest on multiple child molestation counts. Source: Getty

Police allege this happened while he was providing private tennis coaching to these children.

Due to that, police now fear that more children may have been impacted.

Meanwhile Mark remained tight-lipped outside his San Diego home, declining to comment on his father's pending trial.

Mark Philippoussis and his father Nikolaos. Source: Instagram

Nick Philippoussis was arrested at his home in a northern San Diego suburb on Tuesday and sheriffs executed a search warrant on the premises.

He is being held in San Diego Central Jail on $US2.5 million ($A3.2 million) bail.

Under California bail laws he will need $US2.5 million ($3.2m) to be bailed out, and if he makes all of his court appearances until his case concludes he will receive the $US2.5m back.

If he uses a bail bondsman he needs to put just 10 per cent down to get out of custody, but he will not get the money back, as the bondsman will keep the $US250,000 ($315,025).