Anthony Seibold has delivered a hefty spray to his Broncos side following their 30-14 loss to Canterbury and warned Parramatta will "beat us completely" in next week's sudden-death final if Brisbane produce a similar performance – assuming they even get there.

Seibold was fuming at the players' attitude after they conceded five tries, including three from kicks, to the gutsy Bulldogs who again proved giant killers in the final quarter of their 2019 campaign.

The loss will leave the Broncos in eighth place with a visit to the fifth-placed Eels looming, although Brisbane would drop out of the top eight altogether if the Wests Tigers and Cronulla play out a draw in Sunday's sold-out clash at Leichhardt Oval. Seibold's men will board a plane back to Brisbane while that match is taking place.

"I'm very disappointed in our group," Seibold said.

"That's an attitude thing, it looked like the Bulldogs were playing for a place in the finals, not us.

"I thought we were well past it, to be fair. They've turned up looking for a soft performance or just dipping the toe in.

"The first set summed it up, we had two offloads against us and two missed tackles. That's an attitude. Now we've got to hope tomorrow night doesn't go to a golden point draw."

Seibold remained frustrated at the prospect of the side not having any control over their own destiny before reflecting on the past three months of results for the club.

The Broncos slumped as low as 14th on the Telstra Premiership ladder before recording six wins and a draw in the final 10 rounds to scrape into the top eight.  

"I'm quite negative at the moment because I'm frustrated with what we dished up tonight," Seibold said.

"If I look at the second part of the year we've made some really big strides but I'm annoyed because now we hope tomorrow doesn't go to a golden point draw. And that's not a good strategy.

"But I'm proud of how we've turned out season. I'm proud of how our members have stuck by us.

"They'll be hurting tonight, I'm hurting and our team is hurting."