The master coach will vie for an eighth NRL title in Brisbane next Sunday against either Penrith or Melbourne, the Rabbitohs being his fourth different grand finalists in a period that stretches across five different decades.

And he used all of that experience in a rollicking post-game press conference that followed a 36-16 win over Manly, where all the focus was taken away from his men and onto his former employers.

The 71-year-old took aim at Brisbane officials over his ugly exit from the club to join Souths at the end of 2018, when he and Anthony Seibold eventually switched jobs a season earlier than planned after Bennett was sacked.

"I will say publicly, they (Brisbane) undermined me in their conversations with Souths," he said.

"They didn't do a little job on me - they did the best job they possibly could.

"To Souths' credit, there were some people there who had worked with me before, they were happy to bite the bullet and give me the opportunity.

"I owe (Souths' owner) Russell Crowe, and hopefully tonight is part of the repayment, what the team has done."

Brisbane had viewed Seibold as the way forward at Red Hill, but now Bennett is in another grand final and the Broncos are still recovering from a maiden wooden spoon last year.

"They felt a lot of things," Bennett said when asked if he felt vindication.

"I wasn't listening to them because I have spent a lifetime being honest with myself and if I thought I was washed up as a coach I wouldn't coach another day because I would let too many people down."

A young Bennett co-coached Canberra to a decider in 1987 before winning six titles with Brisbane and then another with St George Illawarra in 2010.

"I am still motivated by the same things," he said of the 34-year journey between grand finals.

"As a 23-year-old, I decided to go and coach a football team because they didn't have a coach.

"If I want to coach then I've got to be good at what I do, I have to adapt. It's as simple as that, no grey areas.

"If I don't want to adapt, then I move on because my time's up."

Set to depart for Brisbane next year, Souths captain Adam Reynolds battled a groin injury that almost forced him out of Friday's win while utility Benji Marshall will play a second grand final 16 years after winning with Wests Tigers.

"He's saved my career two times," Marshall said of Bennett, who recruited him to Brisbane in 2017 and then again to Souths this year.

"It's the care factor in feeling loved and (having the) confidence of your coach.

"He just loves coaching; the way he talks to the team, he still has the touch ... I think he gave himself goosebumps this week.

"I love Wayne."

Australian Associated Press