Darren Lockyer guided Brisbane into the grand final with what the Test skipper described as the club's greatest play-off win, a stunning 37-20 NRL preliminary final victory against the Bulldogs at Aussie Stadium.

The Bulldogs were seemingly on course for their second grand final appearance in three years after building a commanding 20-6 halftime lead until the Broncos produced the third biggest comeback in finals history.

The Broncos will play the winner of St George Illawarra's clash with Melbourne after scoring six unanswered second-half tries, with Lockyer the chief architect.

The former Golden Boot winner scored a try, set up several others and kicked a field goal to bury the Bulldogs and raise hopes of a sixth premiership.

"I don't remember one better in a finals game," Lockyer said when asked if there was a more emphatic September victory.

"To do that in a Broncos jersey, I don't remember one better."

Only Newcastle, who overcome an 18-point deficit against Parramatta in 1997 and the Bulldogs, who gave the Eels a 16-point start the following year, have registered bigger come-from-behind finals victories.

The only bad news for the Broncos was Petero Civoniceva's 57th minute high shot on Bulldogs superstar Sonny Bill Williams, which was placed on report by referee Paul Simpkins and will be scrutinised by the match review committee on Monday.

The Test prop said he would be "heartbroken" if he missed the decider through suspension, but received support from Williams.

"Hopefully he doesn't miss Shane Webcke's last game and I wish him all the best," Williams said.

After scoring early, the Broncos conceded three tries to go into the sheds 14 points behind, where some home truths were administered by coach Wayne Bennett.

"At halftime, Wayne actually mentioned it, to keep the faith," Lockyer said.

"In the last couple of months of footy when we're behind we panicked a bit but tonight we kept our nerve and a couple of early tries in the second half really got us going again.

"Everyone in the team at halftime still believed we could do it.

"He told us to keep the faith - just be the Broncos."

Asked what he said at halftime, Bennett said: "Nothing that made a lot of sense.

"What happened tonight, we were probably lucky, we were lucky to get away with it."

The Broncos lifted when Shaun Berrigan scored his second try five minutes after the resumption, a magnificent 100-metre effort begun by Justin Hodges.

That was the catalyst for a remarkable turnaround, as Dane Carlaw, Darius Boyd, Lockyer, Brent Tate and then Corey Parker also crossed in the second half.

"You never think you're in a grand final, especially playing a side like Brisbane in such an important game of the year," Bulldogs captain Andrew Ryan said of the squandered lead.

"We knew it wasn't over at halftime."

Lockyer was everywhere in the second stanza, prompting questions about whether he'd earned the mantle of the best player in the game. But Bennett wasn't biting.

"Darren Lockyer in his own right is a fine player," he said.

"Whether he's the best - who can definitely say that?

"All I know is he's a wonderful player for this club, he's a champion player for us."

Bulldogs pivot Daniel Holdsworth sustained a 17th minute ankle injury and didn't return, although his presence would have had little effect on the Broncos onslaught.

"It certainly wasn't ideal," Bulldogs coach Steve Folkes said.

Brought to you by AAP © 2024 AAP