Ex-AFL player denies assault claims

Nick Stevens' girlfriend's mother had to step between the pair to stop the former AFL player headbutting her, a court has heard.

The Ringwood Magistrates Court was also told the former Carlton and Port Adelaide player slammed his then partner's head into a brick wall at her parents' home, a claim his lawyer called "patent nonsense".

Stevens has pleaded not guilty to 30 charges of assaulting the woman while they were in a relationship.

The woman's mother said on Wednesday she had to squeeze between the pair during a fight at Stevens' Sorrento property to stop him headbutting her.

"Nick went forward to headbutt (my daughter)," her mother said.

"I got very frightened."

The woman told the court he slammed her head into a brick wall and punched her during a number of alleged incidents in 2012 and 2013.

"(There's) a dent in my cheek that I see every day when I put my make-up on," she told the court on Wednesday.

"It's just hard to relive."

Stevens' lawyer Serge Petrovich asked the mother if she had ever seen headbutts in real life, and she said she might have seen them on the sports field.

Mr Petrovich also said the woman had made up the details of an incident in which Stevens allegedly smashed her head into a brick wall at her parents' home.

"What I'm saying to you is that's just patent nonsense," Mr Petrovich said.

"That's not correct," the woman replied.

A former partner of Stevens' ex-girlfriend also appeared in court, and was asked about their drug use. He said he had seen the woman use ecstasy twice while they were together.

He said he received a phone call from the woman when she and Stevens were having a fight.

"She said, 'Get away, get away. You're a psycho. Leave me alone'," he said.

The woman's father told the court he twice drove to Stevens' home after receiving phone calls from his distressed daughter.

He showed the court more than a dozen photos of his daughter with bruises on her face, arms, hips, spine, hands, knee and neck, which were taken after an alleged incident on February 10, 2013.

The woman told the court she had promised Stevens she would stay with him so he could get help.

The hearing continues on Thursday.