Drug kingpin Tony Mokbel remains in a serious condition in hospital as police deflect suggestions the prison yard attack that nearly cost his life was a gangland hit.
Royal Melbourne Hospital on Thursday listed the condition of the 53-year-old as serious, three days after he was allegedly stabbed by two inmates at maximum-security Barwon prison.
The pair have been charged with attempted murder and other offences.
The attack allegedly involved homemade weapons, shaped into makeshift knives or shivs with one reportedly hidden in a zucchini.
Victoria Police Chief Commissioner Graham Ashton refused to confirm the attack was the result of Mokbel's underworld links.
"That's a bit of a stretch to jump to gangland hit in that case. At this stage the most likely theory is around inter-prison feuding," he told ABC radio on Thursday, pointing to ructions within Barwon.
Mr Ashton also declined to draw links between Mokbel's stabbing and the 2010 killing of fellow gangland identity Carl Williams, who was murdered in the same prison.
"We're a long way from forming those sort of conclusions," Mr Ashton said.
"Every case has to be taken on its merits. We need to try and get to why."
Monday's attack occurred a day after a newspaper report that Mokbel intervened in a standover racket run by Pacific Islander inmates.
A second victim, aged 31, was also injured but is back in jail after spending Monday night in hospital.
Corrections Commissioner Emma Cassar said it was too early to say what prompted the assault, including whether there was a powerplay within the jail.
Premier Daniel Andrews said the government would not rule out changes to prison operations in the future, pending the outcome of a probe into what happened.
The alleged attackers are due to face Geelong Magistrates Court on Friday accused of attempted murder, intentionally causing serious injury and causing serious injury intentionally in circumstances of gross violence.