Jones, now 85, is standing trial in the NSW Local Court after pleading not guilty to 20 counts of indecent assault and two counts of sexual touching without consent.
Six men allege they were non-consensually kissed, groped or subjected to sexual misconduct by the former talkback host between 2003 and 2023 in Sydney and the NSW Southern Highlands.
One of the complainants is a former radio staffer who claims he was repeatedly kissed and groped by Jones without consent over five months when they worked together.
He previously told the court he broke down while confiding in prominent 2GB talkback host Ray Hadley that he had been indecently assaulted by Jones a decade earlier.
Hadley entered the courtroom on Tuesday afternoon to give evidence in the hearing.
He did not make eye contact with Jones as he walked in but glanced at his former rival once he was in the witness box.
Hadley asked the radio staffer if he was OK and listened as the younger man disclosed the alleged indecent assaults, the court was previously told.
"I just broke down sobbing," the former radio staffer said emotionally.
"I said, 'He's a f***ing grub. He used to grab me on the cock.'"
The man said he refused Hadley's offer to go to police together, instead swearing the 2GB mornings host to secrecy.
"I didn't want anyone to know," he told the court.
The radio staffer revealed the alleged indecent assaults to Hadley after learning journalist Peter FitzSimons was researching similar allegations about Jones.
Although he didn't want to be identified, the radio station staffer said he wanted FitzSimons to know there was some truth to the claims.
Jones's barrister suggested the staffer was encouraged by Hadley to make a complaint against Jones to "destroy" his rival.
But the staffer strongly denied coming forward to benefit Hadley.
"I know they didn't like each other but they weren't rivals," the radio staffer told the court, later describing tensions between the two as a "beef".
But a former colleague told the court on Tuesday that Hadley and Jones were locked in a contest for the coveted breakfast radio slot at the time.
"There was a fierce power struggle going on between the two hosts and there was no middle ground to be had," he said.
He said he was told Hadley signed a "secret contract" to replace Jones when the veteran broadcaster's agreement was drawing to an end.
The "ploy" ultimately didn't come to fruition because the chairman of Nine - which owned 2GB - stepped in to save Jones and prevent Hadley from hosting the breakfast show, the former colleague said.
Jones retired from radio in 2020, four years before he was arrested and charged with the offences before the court.
The former Wallabies coach has denied the charges.
The offences are all alleged to have occurred during the latter part of his 35-year broadcasting career, when he dominated Sydney's airwaves.
The once-powerful, commanding voice in the court of public opinion also broadcast to a national audience for years as a regular commentator on Nine's Today program and as a host of a show on Sky News.
The trial is expected to run into November.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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