The Canterbury Bulldogs will be forced to play without Jacob Preston over the coming weeks after scans confirmed he has suffered a hairline fracture of the jaw.

The second-rower sustained the injury during the Bulldogs' narrow Good Friday loss to the South Sydney Rabbitohs in a head clash during the second half.

The incident left Preston motionless on the ground for a number of seconds, with the forward then eventually being taken from the field for a head injury assessment by club medical staff.

Despite the fact Preston had been on the ground, the club only ruled his symptoms as Grade 2, meaning he could undertake a head injury assessment, and, upon passing, return to the field.

The NRL's independent doctor in the bunker has the power to overrule club medical personnel and upgrade a concussion to Grade 1 symptoms, however, no decision of the sort was made during Friday's game.

That meant Preston was able to return to the field, however, it has now been revealed by The Sydney Morning Herald that Preston in fact played the remainder of the game through a hairline jaw fracture.

Scans on Saturday morning confirmed the damage to Preston's face, with the report suggesting he will now miss at least three weeks of action for the blue and white.

The boom youngster's absence will be joined by that of Josh Addo-Carr for next week's clash with the Sydney Roosters after he sustained Grade 1 concussion symptoms in an ugly collision with South Sydney fullback Latrell Mitchell on the stroke of halftime.

Addo-Carr will be subject to the 11-day mandatory stand-down in a bitter blow for the Bulldogs, and the winger, who only returned from injury during the game against South Sydney.

Preston missing the Roosters game will likely be joined by missing Round 6 away from home against the Melbourne Storm and Round 7 at home against the Newcastle Knights, before he is a chance to return in Round 9 against the Wests Tigers after a bye.