That would give Luke a role as back-up, and potentially a scenario where they are both on the field at the same time.
It's a good move for Luke.
He wanted to stay in the NRL, but cap issues were complicating the situation for several clubs.
There was also interest from some Super League franchises, but Luke's first choice was to stay in the southern hemisphere.
Sydney is also familiar for Luke and his family, after his long stint with the Rabbitohs.
Luke made his NRL debut in 2007 and played 188 games for South Sydney, before his move home in 2016.
He struggled for consistency in his first two seasons at Mt Smart, but enjoyed some vintage displays in 2018 and was one of the best in the squad.
Last season was a mixed bag, as he performed well some weeks but other times was relegated to reserve grade.
The 271-game veteran remains a clever distributor and dynamic runner from dummy half and is a strong defender.
He has a solid kicking game, while he is also a handy goal kicker.
In August Warriors coach Stephen Kearney admitted Luke's chances of being at Mt Smart next year were remote but said he still had much to contribute at NRL level.
"When he is playing well and playing his best footy, he is an asset for any footy team. But he has to be at his best," said Kearney. "He's been a wonderful servant for the footy club and for rugby league."
Around the same time, after the last Warriors home game, Luke admitted he had an open mind about his future.
"I loved my time here, always loved New Zealand," said Luke. "If it ends up I have to find somewhere else, so be it. Our little family is happy to move on. If I have to go to Australia to play, I'll put my hand up."
