Jacob Preston is knocking on the door of State of Origin, but according to rugby league great Paul Gallen, he still has two men to get past before his name goes down in Blues contention.

Speaking on Channel Nine's post-game broadcast following Thursday night's clash between the Canberra Raiders and Canterbury Bulldogs, Gallen acknowledged the impressive form of the young Bulldogs forward who scored the game-sealing try to win the game over the Raiders.

Gallen revealed where Preston sits in his pecking order.

"I couldn't have him in front of Liam Martin ... and even Hudson Young," Gallen said.

The Blues legend pointed to positional specifics, as well as sharing that the Panthers back-rower is his favourite back-rower in the game, for his reasons why Preston is not high on his list.

"Hudson Young plays on the left edge, and Liam Martin plays on the right edge," Gallen continued. 

"I can't have [Preston] in front of those two."

It's a significant endorsement of Martin and Young, the Raiders' back-rower, who didn't have a strong game against the Bulldogs. 

Gallen stopped well short of closing the door on Preston putting on a Blues jersey, leaving the door ajar with a conditional stamp of approval. 

"If he keeps playing the way he is, he'll put his name in the 17," he said. 

With Preston being part of the Origin camp in January and joining the camp in the middle of the Origin series last season, should Preston maintain his current trajectory, the selection headache for NSW may grow deeper as Origin approaches.