The 22-year-old has been released from the final year of his contract with the Rabbitohs after being tempted to the Bulldogs by the lure of a consistent shot at playing fullback.

Allan deputised for Souths star Latrell Mitchell at the back end of 2020, scoring four tries and providing five try-assists when he was switched from wing to fullback in the final six games of the year.

His blistering form resulted in him making his State of Origin debut for Queensland.

Joining the Bulldogs immediately under coach Trent Barrett, Allan will slot straight into a new-look backline that includes Nic Cotric and Kyle Flanagan.

"We have worked hard in the off-season to sign the right players in terms of their ability and attitude and we believe that Corey will be a great addition for our club," Barrett said.

"Everyone has seen what Corey can do over the past two seasons and we believe that he has the potential to be an outstanding player and someone that adds both quality and versatility to our backline.

"Corey will join us immediately and start training with the squad from today and everyone is looking forward to him being part of the Bulldogs."

Allan's preferred position is fullback and he will have a clearer shot at the jersey at Belmore.

His release from the Rabbitohs is likely to clear up space for them to sign unwanted Penrith winger Josh Mansour, who has one year left on his $500,000 deal.

Mansour played lower grades for the Rabbitohs and they could pick him up at a bargain price if the Panthers chip in some of his contract.

Meanwhile, the Panthers have signed Cronulla forward Scott Sorensen on a one-year deal.

His addition will bolster the forward pack after the grand finalists lost James Tamou and Zane Tetevano at the end of the 2020 season.

Australian Associated Press