Sharks prop Andrew Fifita against the Dragons in Round 23.

NRL Premiership-winning prop Andrew Fifita believes he is one indiscretion away from having his Cronulla Sharks contract "ripped up".

Despite leading his side to grand final glory earlier this month, Fifita was not selected for the Kangaroos Four Nations squad for publicly supporting convicted one-punch killer Kieran Loveridge. 

Fifita said he hadn't spoken to Loveridge since their friendship became public. 

The 27-year-old condemned Loveridge's actions, labelling them as "wrong" and said that it had taken him two-and-a-half years to forgive him.

Speaking on Sky News on Tuesday night, the Sharks front-rower said he felt his future in the game was in jeopardy. 

"For myself, to be honest I think it's a punishment," Fifita said. 

"I feel like I'm on my last chance with the NRL. They all know that, I know that. 

"I'm thinking the worst at the moment. I've got one more mess-up and I'm out – my contract is ripped up."

While he won't feature for Australia on the UK tour, Fifita was allowed to see out the Telstra Premiership season despite the ongoing investigations. 

He said the last few weeks of the year were a difficult time for him and his family, and while he managed to put on a brave face on the field, the emotional toll was almost too much to take at home. 

"I think it was the week before the Storm, we were playing for the minor premiership and all of it came out," he said. 

"I just started knuckling down and I kind of got through that game, but still, everyone heard the boos, everyone heard everything else. 

"As we lined up against Canberra [the following week], the club were finding it hard to keep me in and it got to a point where it got that real. I broke down to my wife at home and said 'I can't do it no more'."

NRL CEO Todd Greenberg made it clear at the Kangaroos squad announcement that Fifita didn't fit the culture the Australian side was trying to promote, but did open the door for a possible return if he took the decision on board and changed his ways. 

"Andrew clearly is a talented footballer and played a key role in the Sharks' grand final victory," Greenberg said. 

"However, we believe that to wear the Australian jersey, the most prestigious jersey in our game, you should have to distinguish yourself both on and off the field. 

"As you know, Andrew is currently being investigated by the integrity unit after wearing an armband supporting someone convicted of a violent offence. While that may not have been illegal, it was in poor taste in the extreme. 

"Our determination is to build a culture in the Kangaroos which every Australian can be proud of, and more broadly, I hope players realise misbehaviour can in future lead to their missing out on their dream of playing for their country. 

"I also hope that Andrew will learn from this decision, deal with his off-field issues and return to the Australian team soon."