Rabbitohs captain Sam Burgess.

Wayne Bennett has told his slumping Souths side that their season is "not terminal yet, but it's getting close", as their sixth loss in the last 10 weeks dropped them out of the top four for the first time this year.

The Rabbitohs were licking their wounds from a 14-6 upset at the hands of Canterbury on Saturday night, with Braidon Burns suffering what is feared to be a season-ending hamstring injury and Sam Burgess also pulling up lame with a recurring quad issue.

Bennett was blunt in his post-match appraisal both publicly and privately.

The Rabbitohs' third loss on the trot sees them fall behind Manly into fifth place on for-and-against, a scenario that will cost them a second chance in the finals if Souths can't rediscover their mojo.

"I just told them in there it's not terminal yet but it's getting close," Bennett said.

"We're not playing our best football.

"We've played some good football this year, we wouldn't be where we are if we hadn't.

"We've just lost some momentum - we did at Origin time and it hasn't come back.''

The Rabbitohs did not get across the line against a determined Bulldogs defence, relying on three penalty goals from Adam Reynolds for points at ANZ Stadium.

Bennett lamented Souths execution with Reynolds and Cody Walker unable to force a repeat set, but said Reynolds was not overly hampered by his ongoing back injury.

Burgess will be racing the clock for next Friday's showdown with Brisbane and former coach Anthony Seibold.

But having returned from a quad strain that ruled him out of last week's loss to the Storm, Bennett sees his inspirational skipper playing in the front row for the rest of the season in a bid to spark the forward pack.

Burgess had been switched to the right edge when Bennett arrived at Redfern to capitalise on his running game and accommodate NSW lock Cameron Murray, but will likely remain in the middle if fit for the Broncos clash.

"We need his leadership out there and he needs to be probably in the middle of the field doing that rather than sitting on an edge," Bennett said.

"I'm trying to give other guys opportunities to take the position looking forward a little bit.

"He's a big player in the club. He's been out for six or seven weeks now. We can nearly say we're used to him not playing with us but that's not the case.

"We want him there [against Brisbane] but it doesn't look great at the moment."