A man who desperately wants custody of his stepson ends up getting into a nasty brawl with his convict wife's ex after confronting him behind her back.

On Friday night's episode of the We TV reality series Life After Lockup, Marcelino and Brittany Santiago are in the midst of fighting for custody of her son, Giovanni, when he a has sit-down with the four-year-old's father Tito Santana.

After exchanging words, Brittany's ex challenges the 40-year-old poker player from Las Vegas to a fight, and things get so heated between the two that one of the show's producers gets shoved out of the way when he tries to pull them apart.

Sit-down: Marcelino Santiago (right) confronts his convict wife Brittany's ex Tito Santana (left) on Friday night's episode of Life After Lockup

Drama: Marcelino wants Tito to give them 100 per cent custody of his four-year-old son Giovanni, whom he shares with Brittany

Like Brittany, Tito is also a convicted felon, but when they sit down, he makes it clear that it's her fault that he has full custody of their son.

'Obviously, Brittany didn't tell you all the juicy details of how it went down that I ended up getting 100 per cent custody,' he says. 'There wasn't no court fight. You know, we didn't fight in court. You know that, right?

'She didn't sign the paperwork. She didn't even f****g show up,' he explains. 'The court just gave it to me. [The] state of Nevada gave a father 100 per cent rights. Now you figure there's something there. So, what are you talking about man?'

'There are certain benefits that come with Giovanni being 100 per cent ours,' Marcelino tells Tito. 'I'm talking about Giovanni's best interests.'

'What are you talking about, man? I'm not gonna give up 100 per cent custody of my son,' Tito hits back, telling him it's 'ridiculous' and 'disrespectful' for him to show up to his house and suggest that.

Not having it: Things quickly get heated between the two, and Tito challenges him to a fight

Altercation: A producer tries to break up the brawl but ends up getting shoved out of the way

Can't be tamed: hey continue to throw punches and wrestle around the living room until they crash down between the couch and coffee table

'I'll be dead before you have 100 per cent custody of my son,' he insists.

Marcelino stresses to Tito that they don't ask him for money, even though Giovanni has been living with them full time.

'Your son has been with me for the last year — with no support from you,' he says.

'I said no,' Tito yells. 'I'll tell you what bro, you ain't have my motherf*****g son for the motherf*****g year.'

'What's March to March?' Marcelino asks, insinuating that's how long Giovanni has been staying with him.

'What part of that don't you motherf*****g understand? You wear glasses. Get a hearing aid,' Tito responds.

Love at first write: Marcelino met Brittany on a prison dating website before they fell in love and got married

Stepdad: Marcelino has developed a close bond with Brittany's son Giovanni (pictured)

Newest addition: In addition to Brittany's son, she and Marcelino have a baby girl named Zoila, who was born in December 2018

'Your speaking to a grown man,' Marcelino tells Tito, prompting him to leap off the couch and start emptying out his pockets.

The two start to take jabs at each other, and when a producer tries to get between them and put an end to the fight, he ends up getting pushed out of the way.

They continue to throw punches and wrestle around the living room until they crash down between the couch and coffee table.

Marcelino met Brittany on a prison dating website, and after falling in love with her and getting married, he developed a close bond with Giovanni.

His fight with Tito is undoubtedly bad news for his wife, who has been focused on staying out of trouble since her release from prison.

In addition to her son, she and Marcelino have a baby girl named Zoila, who was born in December 2018.