A former professional boxer bashed and tried to rape a young Japanese tourist in the stairwell of a Melbourne block of flats before shaving his head for disguise and going to church to pray for forgiveness.

Philippines-born Rey Anton Olarte, who fought in 51 fights, pleaded guilty in the Victorian County Court on Wednesday to attempted rape and intentionally causing injury over the August 2016 attack on the 23-year-old woman.

Prosecutor Ray Gibson said Olarte, 34, grabbed the young woman from behind as she waited for a lift before dragging her by the ankles to an alcove and punching her in the face and stomach, repeatedly smashing her head against a concrete wall and forcing himself on her as she screamed for help.

Olarte, who saw his last fight take place in 2014, was mostly used as a durable journeyman in Australia and the Philippines. He ended his career with a record of 18-24-9, 4 KOs. Many promoters used him, because he was very durable (only 5 stoppage losses) and at the same time he wasn't a puncher.

He fought a who's who of fighters from that side of the map - including Michael Zerafa, Lenny Z, Billy Dib, Josh King, Naoufel Ben Rabeh, Gairy St. Clair, Andrew Wallace and several others.