Mitchell Moses has told Parramatta's rivals he will be staying put at the Eels, ending months of speculation around his future and offering long-term security to his club.

Moses made the call hours out from the grand-final rematch against Penrith and a month after the round-one deadline he had set himself in the off-season.

With a field goal in extra-time on Thursday night, Moses sealed the Eels' first win of the season to showcase the kind of ability Parramatta are paying top dollar to retain.

Post-match, coach Brad Arthur said the deal had not yet been finalised but that Moses' intentions were clear.

"Nothing's been confirmed," he said.

"Obviously, he knows what he wants to do and you could see he was thinking very clearly tonight.

"He's been under a bit of pressure but he responded in the best way possible."

Moses already had an option in his favour for next season, but the new deal will keep him at the Eels long-term.

The extension comes after Moses was offered significantly more money to move back to Wests Tigers, the joint-venture club hoping he would turn their fortunes around.

The Sydney Roosters were forced to deny speculation this week they were interested in the playmaker, while Canterbury were at one stage another potential suitor.

At different stages Moses also hit back at suggestions he was greedy or handing too much power to his management, as Parramatta slipped to an 0-3 start.

But Moses decided to stay loyal to the Eels.

His signature comes after five-eighth Dylan Brown signed a new deal with the NRL club in January, locking him in until 2025 with an option in the playmaker's favour to extend it to 2031.

Fullback Clint Gutherson and coach Arthur are also with the Eels until the end of 2025.

With Moses as their halfback, Parramatta have won 76 of 134 games since his mid-season arrival from the Tigers in 2017, with the high point being last year's grand-final appearance.

Moses had starred on the run to that decider, including missing the birth of his first child to play in the preliminary-final win over North Queensland.