North Queensland's Tom Dearden will make his State of Origin debut after Queensland playmaker Cameron Munster was ruled out of next week's decider.

Just over a year after he was a Brisbane NRL discard, North Queensland half Tom Dearden is set to make his State of Origin debut in next week's decider.

Queensland coach Billy Slater confirmed on Saturday the Maroons have suffered a major setback with star playmaker Cameron Munster and winger Murray Taulagi both ruled out after testing positive to COVID-19.

Dearden will now move into the Maroons' 17, although whether he starts at five-eighth in place of Munster or comes off the interchange bench with Ben Hunt to start at No.6 is yet to be determined.

Brisbane winger Corey Oates will replace Taulagi on the left wing.

"It's certainly not ideal to have this sort of disruption leading into a decider," Slater said.

"Cameron Munster is a great player. I really feel for him and Murray because they both worked really hard to get their opportunity to play in a decider.

"It could be the game of their life and they're sitting in a hotel room right now.

"It doesn't seem fair, but that's the position we're in.

"We're really comfortable with the replacements that have come in."

Dearden's elevation comes just over 12 months after he moved to the Cowboys having been put on the scrapheap by the Broncos.

While Slater admits it is a huge blow to lose a game-breaking talent such as Munster, the Maroons coach is confident Dearden will prove his worth against NSW at Suncorp Stadium on Wednesday.

"There's a lot of things that I like about Tom ... it's not any one thing," Slater said.

"He's a really good defender. He's a great competitor, uses the footy well.

"He's a big reason why the Cowboys are playing the sort of footy that they're playing.

"We like those habits in our players."

Despite losing Munster and Taulagi just days before the game, Slater didn't believe the setback would bring heavier restrictions on the squad to avoid exposure.

"We were all cleared this morning so that's a really good start, but we're certainly not out of the woods," he said.

"It's everywhere ... it's a really tough situation for everyone and we're not immune to it.

"Whoever performs the best out there in the 80 minutes on Wednesday night will come away with a shield.

"That's all we can control. That's all we focus on.

"It's far from ideal this preparation but it's the hand we've been dealt ... Queensland will be proud of this team."