The English midfielder made unwanted phone calls and threats to Ainsley McRae after she told his girlfriend of over five years about their relationship.
Paisley Sheriff Court heard how Bartley met Miss McRae, 25, through Facebook and the pair began chatting before meeting up in person.
Matters came to a head on January 13 this year when Bartley’s long-term girlfriend noticed a message from Miss McRae on Facebook which revealed she and Bartley had been meeting up and messaging each other.
Bartley, 31, told the court he ducked out of Hibs’ training to phone Miss McRae, 25 before driving to Glasgow once the training session was over to confront her. He turned up at her workplace, in Glasgow city centre, but was told she was not there.
He then told her in an “angry” and “aggressive” phone call he would try and ruin her life before adding: “Protect the people around you.”
He shouted and swore at Miss McCrae, of East Kilbride, leaving her so scared that she was in floods of tears and was shaking so much her teeth were “chattering,” court heard.
Miss Mcrae said he told her he’d tell his girlfriend about them but did not - prompting her to message his girlfriend to break the news as “she had a right to know.”
Yesterday, Bartley gave evidence, saying he and his long term girlfriend “were on a break” at the time he met Miss McRae.
He said he told Miss McRae he had a girlfriend, and only ever met her twice before going to her work and phoning her a few times on the day in question.
He described himself as “a polite young gentleman” and denied he was “angry” with her for telling his girlfriend about them, adding: “I was disappointed.”
But Sheriff Seith Ireland convicted him of breaking Section 38(1) of the Criminal Justice and Licensing (Scotland) Act 2010 by behaving in a manner which would be likely to cause a reasonable person to suffer fear or alarm.
He said: “I find, beyond reasonable doubt, the accused is guilty of this offence. In my view Mr Bartley can’t be described as a credible and reliable witness.
“I accept everything Miss McRae says about what took place in the relationship, as it turns out, and the phone calls and behaviour of Mr Bartley.”
The judge fined Bartley £400 for the offence.
Bartley, of Penicuik, signed for Hibs in 2015, from English side Leyton Orient.