JOHNATHAN Thurston burst through his front door, his whirlwind tour of Western Sydney over.

“We are moving to Penrith,’’ Thurston beamed.

“I just agreed to a three-year deal with the Panthers.’’

SO LONG: JT farewells fans in style

media_camera JT was ready to walk away from Townsville in 2013.

It’s 2013 and the off-contract superstar has returned home to tell his future wife Samantha that he has just completed a $3 million dollar deal to join the Penrith Panthers.

“Like hell you have,’’ Samantha said.

“We are not moving to Penrith. I hope you can get out of it or you will be living in Sydney on your own.’’

media_camera Thurston and Samantha at the 2013 Dally M Awards.

This is the untold story of how Samantha stopped arguably the game’s greatest player from making the NRL move that would have denied him a fairytale premiership win with Cowboys. Of how a threat prompted the backflip that will mean Thurston retires from rugby league as a North Queensland legend.

And of how a pregnant partner trumped Phil Gould, one of the NRL’s most powerful men.

“I had agreed to go to Penrith when I was coming off-contract in 2013,’’ Thurston said.

“I had made the decision that I would leave the Cowboys and go to the Panthers. I had just been down to Sydney to meet Gus and do the tour of the club.

“Before I got on the plane to come home I told my manager (Sam Ayoub) to do the deal. I was going to become a Penrith Panther.’’

Or so Thurston thought.

media_camera Thurston and Samantha, with Lillie, 10 months, Frankie, 4 and Charlie, 2. (Zak Simmonds)

“I had just fallen pregnant with our first child Frankie,’’ Samantha said.

“I was having a bit of a rough time and I was adamant about not going to Sydney. My support network was in Townsville and I was still working here. There was no way I was going to go to Penrith. I told him he was going to be going on his own.’’

Thurston thought his deal with Penrith was done. He had not signed a contract but he had agreed. And Thurston is not a man who goes back on his word.

“I went to bed that night thinking I was going to be living in Sydney on my own,’’ Thurston said.

“It is fair to say I didn’t get a lot of sleep.’’

media_camera Yet another Dally M medal in 2015.

Rugby league history was about to be rewritten.

Would Thurston go on to win a record-equalling third Dally M medal in 2014?

Would he win a record-breaking fourth in 2015?

He certainly would not have won the Clive Churchill Medal and the NRL premiership with the Cowboys in 2015.

“I called Sammy (Sam Ayoub) the next morning,’’ Thurston said.

“I told him what had happened and that I would probably have to move to Sydney on my own.’’

media_camera Cowboys fans would never have had this moment. (Cameron Spencer/Getty Images)

Ayoub laughed before saving Thurston’s North Queensland rugby league legacy.

“He told me that he hadn’t gone back to Gus with my agreement,’’ Thurston said.

“Sammy said he knew I might end up changing my mind and he wanted to give me a night to sleep on it before making it official. I was so relieved.’’

And with that Thurston drove himself to Dairy Farmers Stadium — now 1300SMILES Stadium — to thrash out the deal that will see him finish his career as a Cowboy on Saturday when North Queensland take on the Gold Coast.

“The deal the Panthers offered me was good,’’ Thurston said.

“And I have a lot of respect for Gus. He had it all mapped out for me. Gus had a plan for me to become a leader at the club and in the community.

“And I would have stuck to my word had Sammy (manager Ayoub) told Gus. I would not have disrespected him or my word if the deal had been done. But turns out he hadn’t been and he saved my relationship.’’

media_camera JT hugs Samantha after playing his last home NRL match. (Ian Hitchcock/Getty Images)

Samantha and JT, married in 2015, now have three children: Frankie 5, Charlie 3, and Lillie 1. Thurston also has a Clive Churchill medal and a premiership win with his beloved Cowboys.

“That old saying is right,’’ Samantha said.

“A woman always knows best. And it just wasn’t because I didn’t want to move to Sydney. Johnathan hadn’t won a premiership with the Cowboys yet and I saw the potential in the team. I knew if he stayed he would win the premiership he had always wanted.

“And even though he played for the Bulldogs, most people consider him largely a one club man. I knew that staying with the Cowboys would pay off in the long term and give him a legacy.’’

Thurston agrees — his legendary legacy sealed with a remarkable field goal in the 2015 decider.

“Looking back it was a sliding doors moment,’’ Thurston said.

“Had my manager told Gus that I had agreed I would not have won the premiership with the Cowboys in 2015.

“Who knows what would have happened with the Panthers?

“But it is a fact that I would not have won a premiership with the Cowboys. That was the defining moment of my career.

“It was my legacy.’’

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Originally published as Thurston: The day I agreed to join Penrith