The 20-year-old suffered a dead arm on his right side early in the game but was forced from the field later on when he tore ligaments and muscle in his left shoulder.
"He was in a real lot of pain after the game and there were concerns it might be structural. We thought he may have hurt the rotator cuff or fractured the collarbone," Bulldogs general manager of football James Fantasia told afl.com.au on Wednesday.
"We got x-rays and that's as good as the news got from there. He didn't have any structural damage but an MRI determined problems with his muscles and ligaments and he'll require surgery to restitch some of those muscle tendons.
"It's a six to eight-week injury. We think the ruling him out [for the season] is the best way because we can get [the surgery] out of the way and he can get himself ready for a full pre-season.
"He was really comfortable with that. He felt it was the best option for him so he can get on with the rehab almost straight away."
Reid, who has had problems with his right shoulder in the past, was playing his first AFL game for the year after undergoing groin surgery at the end of last season.
He also found out he is a type 1 diabetic in November and has spent the pre-season and the past six VFL games learning how to play with his disease.
Meanwhile, the Bulldogs are set to name skipper Brad Johnson for Sunday's clash with Carlton and will give the veteran every chance to prove his fitness after he hurt his ankle on Friday night.
"We're confident he will come up," Fantasia said.
"He was pretty sore on Sunday after the game. He was probably a little bit better but still tender and had swelling on his ankle on Monday at recovery.
"Since then, the swelling has gone down and he's moving a lot freer so we're just monitoring that and we think he'll be right, but we'll make the call later in the week."
Johnson said on the weekend his achilles, which he has battled with this year, felt quite good and he expected to be available to face the Blues.
"I copped a nice little tackle from [Hawthorn's] Cyril Rioli and it got caught under me a little bit," Johnson told Channel Seven on Sunday.
"I'm hopeful I'll be all right, we've got a nine-day break, I just tweaked it a little but and I'm sure it will pull up OK.
"I wouldn't say I'd miss anything. We've got a big break and plenty of time up my sleeve to get things right."
Ruckman Will Minson is rated a 50-50 chance to take his place in the side after injuring his lower leg against the Hawks.
"He went back on after the injury but the concern with Will is he has fractured his tibia before and this soreness is in a similar place," Fantasia said.
"We were concerned earlier he may have a fracture but that's come back all clear.
"It will be more about how much the swelling goes down. If Will doesn't come up, it will certainly open the door for Jordan Roughead as he's been in good form."
Veteran Jason Akermanis will play his second game at VFL level as part of his agreed club-imposed sanction.
Fantasia said Akermanis would be available for selection for the Dogs' round 16 clash with Port Adelaide and would be considered to make the trip to Darwin "if his form and fitness warranted it."
