Minutes after convicted drug lord Tony Mokbel was brutally stabbed in a prison yard, one of his attackers told the other "happy birthday bro".

Key points: Mokbel was punched in the head, knocked to the ground and stabbed seven times with an improvised prison weapon

Mokbel was punched in the head, knocked to the ground and stabbed seven times with an improvised prison weapon The attack came a day after a newspaper article called Mokbel an enforcer

The attack came a day after a newspaper article called Mokbel an enforcer The court was told Mokbel passed a piece of paper to Tiera Bennett about an hour before the attack

Teira Bennett and Eldea Teuira were both 21 when they launched the frenzied attack on Mokbel after a birthday party in Barwon Prison in February 2019.

About an hour before the attack, Mokbel had passed a piece of paper to Bennett, who went back to his cell and appeared to read it.

Graphic CCTV footage aired in court showed the sudden attack, which happened as Mokbel was returning from a visit.

Bennett punched Mokbel's head and knocked him to the ground before Teuira pulled out an improvised weapon and stabbed his victim.

"Teuira pulls a 'shiv' from his shorts and crouches over Mokbel and appears to be stabbing him in a frenzied motion up to seven times," prosecutor Kristie Churchill told the Victorian County Court.

Mokbel suffered life-threatening injuries in the attack, including skull fractures. ( Supplied: County Court of Victoria )

Bennett and Teuira have pleaded guilty to causing serious injury intentionally in circumstances of gross violence and causing reckless injury to another inmate stabbed during the attack.

During the stabbing, the other man kicked Mokbel in the head three times and then retrieved another shiv and hit him in the upper body.

Several of Mokbel's teeth were knocked out in the assault and he was left with displacement of the brain, skull fractures and stab wounds.

The injuries were life-threatening and if Mokbel had not received swift emergency treatment, he could have died.

The court was told Bennett attacked Mokbel with a 'shiv' hidden in his shorts. ( Facebook )

The shivs were made from sharpened wire and a fork.

"You're not an enforcer, this is what you get for talking to the screws you f***ing dog," a prisoner officer heard Bennett yell.

"You think you're an enforcer, well you are f***ing not you c***"," another officer heard Bennett say.

After guards got Bennett on the ground, he yelled out "well done cuss, G-Fam", and Teuira replied "yeah, happy birthday bro".

The attack came a day after a newspaper front-page article called Mokbel a "prison big wig" and a "top enforcer" who had disrupted an extortion racket run by Pacific Islanders in the prison.

The Herald Sun called Mokbel a "prison big wig". ( Twitter: Nick Papps )

Teuira's lawyer told the court his client was supported in court by his parents and other family.

He received "bad treatment" at the hands of older cousins when he visited the Cook Islands as a youngster, but details were not revealed in court.

Teuira, now 22, was diagnosed with post-traumatic stress disorder and has a lengthy criminal history.

Judge Liz Gaynor said Teuira had "a pattern of entrenched, violent behaviour".

AAP