NRL premiership centre Kirisome Auva'a has avoided a conviction or jail for a serious assault on his former girlfriend in Melbourne in January.

The court heard the former Melbourne Storm junior threw her against the walls of a garage and punched holes in the walls of her home, during a violent outburst after a day of heavy drinking at a wedding.

Auva'a now plays for the South Sydney Rabbitohs and scored a vital try in this year's NRL grand final against the Canterbury Bulldogs.

He pleaded guilty to two charges of recklessly causing serious injury and criminal damage.

Auva'a was accompanied to court by the club's manager Mark Ellison, and his lawyer told the court the club has worked hard to get their player back on track.

The court heard the 22-year-old is being counselled once a week and has enrolled in a men's behavioural program.

Auva'a's lawyer said the club had even sought to have domestic violence organisation the White Ribbon Foundation take him on as an ambassador.

The offer has so far been refused.

The court heard Auva'a has also undergone treatment by Relationships Australia for anger management issues.

Magistrate Kate Hawkins told Auva'a his status as a privileged, high-achieving sportsman came with an obligation to be a role model.

"It's a huge problem in our community ... one person is murdered, or dies each week," Magistrate Hawkins said.

"There's much you can give back to the community in the long term.

"As you grow as a man it is very important you take that responsibility on board as much as you can."

Magistrate Hawkins described Auva'a's offending as 'devastating'.

"As a professional sportsman you're very much in the public eye," she said.

"I'd encourage you to become a White Ribbon ambassador ... as a role model, a man standing up and taking responsibility."

Auva'a's ex-girlfriend shocked by attack

In her victim impact statement, Auva'a's former girlfriend said she felt "sad, alone and stressed" after the assault.

"I felt extremely numb," she wrote.

"I'm so hurt and confused someone I thought loved me could hurt me."

She wrote, she spent several weeks hiding the bruises from the attack, and no longer felt safe in her own home.

The court heard Auva'a has written a letter of remorse.

His lawyer asked that he not be convicted.

"Family violence is completely unacceptable and won't be tolerated by the courts or the community," Magistrate Hawkins said.

But said she accepted he had taken responsibility, and had a bright future.

Auva'a avoided conviction.

He was fined $3,000, to pay to the Melbourne Magistrates court fund, and placed on a two-year good behaviour bond.

He will join his South Sydney team-mates at a high-altitude training camp in Arizona next week.