Defence counsel Eric Forster and Nicola Graham expect to call three witnesses, Mr Forster said.
He said Gerbes accepts it was she who picked up a knife from a kitchen bench as the couple argued moments before a 15cm wound was inflicted to Mr Jones' upper abdomen.
The attack severed two crucial blood vessels causing his eventual death from the bleeding that followed.
They had exchanged slaps and punches earlier but Gerbes said she picked up the knife to defend herself and had no intention of stabbing her boyfriend, both the prosecution and defence told the jury.
Gerbes claimed that while she did not know exactly what happened at the moment the wound was inflicted she said Mr Jones had pulled the knife towards himself.
"The defence position is that she did not stab him, that he pulled the knife into himself, either accidentally or intentionally," Mr Walker said.
"The Crown does not accept that version," he said, adding that the angle of the wound did not fit with her claim, which was made in an interview with police and in a re-enactment in the flat, both of which were recorded and are being played to the jury during the trial.
He said the couple had been in a relationship about 17 months, but there had been "ups and downs," some more violent than others, and it had gone both ways.
"Ms Gerbes was willing to stand-up for herself," Mr Walker said.
The incident in which Mr Jones was stabbed started with an argument while the couple was in bed after a night out and according to Gerbes, Mr Walker said, happened in the lounge after she tried to lock Mr Jones out when said he was going out to another bar to find another woman, Gerbes told police.