Watch: Moment tough-talking judge dishes out brutal message to laughing thugs

In an extraordinary verbal blast at their sentence, a tough-talking Melbourne judge has slammed two "cowards" who had stabbed drug lord Tony Mokbel.

Teira Bennett and Eldea Teuira, both 22, bashed and stabbed Mokbel with makeshift shivs about eight times at Barwon Prison on February 11, 2019, following Bennett's 21st birthday party.

The young thugs had earlier laughed like banshees during their County Court of Victoria sentence.

But Judge Elizabeth Gaynor left the two men and courtroom stunned into silence after "departing from the script" and delivering some brutal home truths about life after prison.

In her eye-opening response, Gaynor blasted the young prisoners, letting fly at how they'll have no friends or family to care about them once "GFAM and the bros" ditch them for good.

"Let me tell you, gentleman, in a few years GFAM and the bros are not going to do it for you ... you're going to want a life," she said.

"You may think you're heroes within the jail but do you think in 20 years' time that's going to matter?

"When you're 40, you'll see what G-Fam and the bros do for you.

"You'll end up drug-addled, lonely, old men."

She then said when Bennett and Teuira get out of jail they will start to see their family settling down with jobs and having children and they will want that too.

Gaynor then warned their family will get sick of them and they'll be all alone.

"But you can't do it. You go back on the gear because all you've got is your mates from jail. And then as time goes on you will have a few relationships. You'll have a relationship here, a relationship there. You'll have six kids by six different mothers," she said.

"It is tragic to see two young lives already crashing dramatically off the rails."

Judge Gaynor painted a grim picture of the lives the men could expect if they continued to offend, labelling them cowards.

"The only reason you are getting any attention is because it was Tony Mokbel. At the end of the day you two young blokes - two on one - mauled and maimed a 53-year old man," she said.

Bennett and Teuira's sentences were combined with their existing jail terms for previous crimes.

Bennett was sentenced to up to 11 years and two months, backdated to August 2017.

Teuira was jailed for a maximum of 10 years and 10 months, backdated to November 2017.

Gaynor on Wednesday said the attack was a direct result of a Herald Sun article, titled "Tony the enforcer", that had come out the day before.

She said the attack was carried out to reinforce the dominance of Barwon's Pacific Islander "G-Fam" prisoner group.

Both men began using drugs including "ice" at a young age and were already serving sentences for violent crimes when they attacked Mokbel.

During the frenzied attack Bennett reportedly told Mokbel, "You're not an enforcer. This is what you get for talking to the screws. You f***ing dog".

As Mokbel lay bleeding, Teuira told Bennett: "Happy birthday bro."