The Catholic Church has accepted legal responsibility for the sexual abuse of a nine-year-old boy by notorious paedophile Gerald Ridsdale in a significant case which could open the floodgates for victims seeking compensation.

After denying any knowledge of Ridsdale's offending before the boy was raped in a confessional box at Mortlake in 1982, lawyers for the church on Friday accepted an amended statement of claim from the victim in the Supreme Court – in effect admitting legal liability for his crimes.

Paedophile priest Gerald Ridsdale.

A 10-day civil trial scheduled to begin on January 29 next year will now focus primarily on the amount of damages the church will pay the victim. A mediation hearing will be held on October 15.

The victim, identified in court under the pseudonym JCB, is suing Ballarat Bishop Paul Bird for negligence on behalf of deceased former bishops James O’Collins and Ronald Mulkearns.