A police officer admits delivering repeated "hammer strikes" but denies beating a man during a Melbourne counter-terrorism raid.

Eathan Cruse is suing the state of Victoria for unspecified damages, claiming he was tethered and bashed in April 2015 when a crack squad made up of officers from across Australia stormed his parents' Eumemmerring home.

The then 19-year-old was arrested on suspicion of involvement with a plot to behead a police officer on Anzac Day the same year, but was never charged.

His lawyers allege he developed chronic anxiety, a depressive disorder and post traumatic stress disorder after the raid. They argue the actions of heavily-armed police, in allegedly striking him while on the floor and slamming him into the fridge, were a "gratuitous use of violence" against a man whose hands were bound behind his back.

A lawyer for Victoria Police has told the trial a NSW officer used "hammer strikes" with the underside of his fist in subduing Mr Cruse, and that the young man made contact with the fridge when he slipped while being escorted outside.