A long-time swim coach at a top private school accused of sexually assaulting a 13-year-old girl in the back of his car will remain behind bars.

Jayden Brian, 31, was charged with nine child sex offences following his arrest while coaching a student session at Melbourne Sports and Aquatic Centre in October.

Charges include multiple counts of sexual assault of a child under 16 and grooming for sexual conduct with a child under the age of 16.

Prior to his poolside arrest, Brian had worked at the prestigious Methodist Ladies' College at Kew for nine years. His employment has since been terminated.

His alleged victim is not a student at the school.

Brian has been in custody since his arrest and applied for bail when he appeared in Melbourne Magistrates' Court via video link on Friday.

The court heard that police allegedly found photos on Brian's phone depicting students in 'compromised stretching positions'.

'Significant' amounts of child abuse material were also allegedly discovered on the phone and Brian's MLC-issued iPad, the Herald Sun reported.

The court also heard that Brian allegedly replied: 'S**t Oh f**k, oh f**k, oh f**k' when told he was under arrest.

Prosecutors allege the complainant was 'groomed' after she and Brian started messaging each other on Snapchat while he was at work in September 2025.

Brian allegedly requested the girl send intimate photos, which he later complimented on when he learned that she was 13, the court heard. 

Later in their chat log, Brian allegedly detailed his 'urgent desires' to have sex with the girl, who requested alcohol and cigarettes in exchange.

The two allegedly met up with each other on September 25 after Brian told his unsuspecting fiancée that he was meeting someone to sell trading cards.

Instead, he allegedly met the girl at an agreed location, where she got into his car.

The pair began chatting before Brian allegedly kissed her. 

This made the girl 'feel weird and awkward', the prosecutor told the court. 

The girl rejected further sexual advances as Brian allegedly kissed her neck and touched her thigh before promising the teen a $50 Amazon gift card.

Afterwards, the girl told friends about what had happened before filing a police report on September 27.

Officers launched a 'covert operation', where police posed as an underage girl to talk with Brian.

The court heard he allegedly sent a number of flirtatious messages to officers, which were among many others he allegedly sent to other girls which were later found on his phone. 

'On the accused's phone are numerous forms of messages sent to underage females on numerous platforms,' the prosecutor said. 

Photos of a second complainant were allegedly found on the phone which depicted her in an intimate state when she was 17-years-old in 2021. 

A 13,000-page brief of evidence has been compiled against Brian.

Senior Constable Max Henning told the court Brian should remain behind bars because he posed 'too much risk … to the vulnerable community'.

He added there was evidence of Brian allegedly talking to underage girls dating as far back as 2018.

No bail condition could 'curb' this alleged offending, the officer said. 

Brian has no prior criminal history and was the 'primary carer' of his fiancée, who is in need of care due to her health.

Brian's defence barrister James McQuillan told the court that both he and his fiancée would live with his father if he was granted bail.

Brian's bail application will resume next week. He remains in custody.