After a week of speculation over his place in the side, Cleary played a crucial role in the lead-up to the Blues' three first-half tries as they levelled the series at ANZ Stadium.
His brilliance highlighted a fiery game that included Payne Haas and Tino Fa'asuamaleaui being sin-binned in the second half for throwing punches.
Cameron Munster was also left in doubt for next week, with the Maroons No6 lasting just two minutes after being concussed following contact from Tyson Frizell.
Cleary entered the game with the unenviable record of being the first NSW half in history to go through his first six games without a try assist or linebreak assist.
It prompted Origin great Andrew Johns to call for his head following the Blues' series-opening loss in Adelaide.
By the end of Game II, Cleary had broken the line once himself and put two players through gaps for tries to go with a late 40-20 kick.
It was enough for Johns to heap praise on Cleary in commentary, after a three-week nightmare that included a grand final loss and Origin criticism.
"A lot of people think he's got a really good character ," Fittler said.
"He's a tough kid, he just handled it.
"It's great for the future of Penrith and the Blues."
After the Maroons crossed first through Xavier Coates, Cleary put the Blues on the front foot when the 22-year-old dummied and stepped his way through the line.
Two plays later Cody Walker spun and fended his way over on the right, as the five-eighth also starred in his own redemption tale.
Cleary's boot was then influential for the Blues' next two tries, as he regularly kicked early to corners.
Josh Addo-Carr's sprinting chase on his first kick gave the Blues field position, before the halfback found a stepping James Tedesco to score.
And when Coates dropped a Cleary kick just before the break, the Blues stripped Queensland for numbers from the scrum and Josh Addo-Carr crossed.
"I think we blocked that [talk] out pretty well this week," Cleary said.
"That's the pleasure of kind of being away in camp, surrounded by a great bunch of blokes, great coaching staff and just have to focus on ourselves.
"It's no different this week. We haven't done anything yet, still got a game to win up in Queensland."
Cleary wasn't alone in playing a key role for the Blues.
Jack Wighton claimed his first Origin try while Jake Trbojevic was damaging in defence, forcing errors with his up-and-under tackles that left Coates stunned.
Tedesco was also superb in his first game as captain, throwing the last pass for a Daniel Tupou try from a scrum
Again, the field position came from Cleary pressure on a Jake Friend kick that went out on the full.
And Walker continued his end-of-season form, grubber-kicking for Addo-Carr's second try as he provided real spark on both sides of the ruck.
Meanwhile, the Maroons desperately missed Munster, who was replaced by Ben Hunt at five-eighth.
They started the game well when Daly Cherry-Evans helped an acrobatic Coates cross with a bullet cut-out pass.
But they lacked spark and struggled for field possession after the first 15 minutes, with Josh Papalii scoring their only other try - again from a Cherry-Evans pass.
Regardless, coach Wayne Bennett insisted they could bounce back for next week's decider in Brisbane.
"They out-enthused us, much better than we were," Bennett said.
"I don't think anyone lost any confidence in themselves. They all know they can play better than they did tonight."
