Anti-lockdown protesters clash with police in Melbourne
Police Association of Victoria secretary Wayne Gatt described the rally as "horrific" and said 10 police were injured with six taken to hospital.
"Significant violence confronted those individuals, we had bottles thrown at their faces; projectiles and rocks. This group came to assault the police," he told 3AW.
"There's a range of injuries from dislocated shoulders, torn pectorals, broken bones (and) noses."
Mr Gatt said the riot squad was not deployed to help uniformed officers in Richmond, despite being in the city on standby.
"They are discussions that we will have with Victoria Police," he said.
"We'll do work in the coming days and during the coming hours just to work out what happened and why those decisions were taken, because the last thing we want is our members to go home with serious injuries."
He said the chief commissioner's decision to shut down public transport on Saturday was the right one.
"Had he not taken that decision, our members would have been confronted with thousands upon thousands of protesters, and those scenes would have been amplified," Mr Gatt said.
Asked about a video circulating on social media appearing to show police pushing over an elderly woman and pepper-spraying her while she lay on the road, he said he had not yet seen the vision.
"I can't comment on it specifically. I'm not going to allow my members to be criticised for the actions of these criminals yesterday, they did the best they could," he said.