Canberra Raiders middle forward and State of Origin debutant Corey Horsburgh has reportedly locked up a long-term contract upgrade at the club.

While "Big Red" is already contracted until the end of the 2024 campaign with a player option until the end of 2025, News Corp are reporting his new deal will keep him in the nation's capital until at least the end of 2027.

It's believed the deal will be worth $2.3 million, putting the forward on around $600,000 per year over the next four seasons.

The lock forward's form has been outstanding during the course of the 2023 season, and after being part of the extended Origin squad for Game 2, the Caboolture-born forward made his debut in Game 3 for the Maroons.

After battling through injuries during previous pre-seasons, a full off-season of training this time around has seen a dramatic uptick in workrate from Horsburgh, who is regularly playing big minutes in the Raiders' number 13 jumper.

Now having played 80 NRL games, his experience is beginning to tell, with the aggressive forward reigning in some of those tendencies this season and becoming a consistent force for Ricky Stuart's side.

In 19 games so far this year, he is tackling at almost 96 per cent, making 115 metres per game, and has added 30 tackle busts and 23 offloads to go with 3 tries.

He hasn't played off the bench since Round 5, and in those games, has only played less than 60 minutes on one occasion.

Coach Stuart has regularly spoken over the development of the 25-year-old, and a new four-year deal would likely see him go past 150 games for the Raiders, having debuted for the club in 2019.