Wally Lewis has recalled the self-doubt before his State of Origin debut, delivering a vote of confidence in Tom Dearden and the "underdog" Maroons.

Billy Slater may not approve of the term, but Wally Lewis says Queensland's State of Origin underdog status has been reignited as he offered shock debutant Tom Dearden some comfort.

COVID-19 finally hit Maroons camp last week, with star five-eighth Cameron Munster and winger Murray Taulagi ruled out of Wednesday's decider in Brisbane.

After enjoying a relatively smooth build-up to game one and two compared to NSW, it's sent Queensland scrambling on the back of a hefty loss in Perth.

Playmaker Dearden, 21, has been tasked with replacing the game-breaking Munster while the in-form Corey Oates has parachuted in to take his place on the wing.

Lewis, a former Queensland coach and eight-time Origin man of the match had raved about Munster's game one performance.

Others went a step further, comparing the pair as former and current greats of the arena.

Lewis admits Munster's absence will hurt at Suncorp Stadium, but not necessarily spell the end for the hosts.

"It's not what you wish for in the build-up but it can and has reignited the underdog status," Lewis told AAP.

"Already people were writing Queensland off but they're a dime a dozen, those instances in Origin, and they can use that.

"There isn't a person in the world that will deny they've been dealt a shattering blow.

"But previous opportunities have been presented to the Queenslanders to prove how good they are and they've taken those."

Hyper-positive rookie coach Slater had refused to channel any of that underdog spirit from the outset of the series, firmly of the belief that his squad is simply good enough to win.

"Everything about Billy's approach has been in a positive manner and I'd expect that would continue, perhaps even at an increased level," Lewis said.

Dearden, who could start in the halves or be used off the bench, might enjoy hearing that even The King had reservations before his debut as a 20-year-old.

"Every Origin player, when stepping up into the role, has questioned our own ability, (wondering) whether we're at a level that's equal to the other players," he said.

"I remember my first Origin game, standing next to Arthur Beetson, playing Ray Price, Mick Cronin, thinking 'I'm just a boy'."

"(Beetson said to me) 'you wouldn't be here if you didn't have the ability' and then I felt 10-foot tall and bullet proof.

"The best thing that happens is when you get that opportunity to prove to yourself that you've got it."

Lewis has been a long-time fan of Dearden, telling AAP before last season that he could be the solution to Brisbane's NRL woes.

Instead the half struggled and was shipped to North Queensland, where he's shed a new skin and flourished in a remarkable turnaround.

"I've loved watching him this season for the Cowboys," Lewis said of Dearden, delivering his own Beetson moment.

"You just recognise that he's got that self-belief now and starting to think 'f***, I can do this'.

"If he has the confidence that it can be reproduced at the highest level of the game, that'll be the difference between him going on to even greater heights."

Lewis has enjoyed the strategic cat and mouse between coaches Slater and Brad Fittler, who found the answers at the selection table after Queensland upset NSW 16-10 in game one.

Unsure how Slater will use Dearden, The Emperor of Lang Park had just one piece of advice.

"When I played we always said 'you have to dictate terms'," he said.

"Play the way you want to, make them react."