The 28-year-old First Constable has undergone three rounds of surgery in a bid to save his leg.
The victim's father, named Steve, said the police officer was "shattered".
"He's shattered that this has happened in his line of work," he told 9News.
"He has a number of issues in relation to circulation and severing of the artery, which occurred from the bullet wound."
The police officer was called to Werribee Mercy Hospital last Saturday morning after a psychiatric patient allegedly threatened staff.
The officer entered the patient's room but was unable to subdue him with capsicum spray. There was a scuffle and he was shot.
He then stumbled into the arms of a nurse and was treated.
His father, who is a former police officer, received the late night call.
"[It's] overwhelming and quite emotional for him too," Steve says of his son's incident. "He's holding up really well and that support is going up a long way to help him get back to full health."
It was a routine call out that's left a young constable with months of recovery ahead of him.
This latest shooting has triggered urgent calls for all frontline officers to be equipped with tasers.
Currently only some special operations teams and regional officers are issued tasers in Victoria. But for years the Police Association has been asking for all frontline members to be equipped.
"The question the government has to ask itself is: is the cost of issuing our police with tasers worth more than the cost of a human life?" Wayne Gatt from Police Association Victoria said.
"We've recruited more police and provided the best technology, best equipment but there's always more we can do," Victorian Premier Daniel Andrews said.
That's an admission that prompted a plea from a father who could have lost his son in the line of duty.
"He went to work to do his job, so did his colleagues, I'm just asking the Victorian government to do theirs now," Steve said.