TEENAGE halfback Mitchell Pearce has received a glowing endorsement from the former Australian Schoolboys teammate he edged out of the NSW side to play Queensland in the State of Origin decider at ANZ Stadium tonight.

Knights playmaker Jarrod Mullen, who made his Origin debut in game one last year and came under heavy consideration for this match, insists his former Australian and NSW schoolboys halves partner will not be overawed by the occasion.

"I was 18 years old and he was 16 when we played together in 2006 and I was amazed at how much confidence he had," Mullen said. "He was kicking off his right and left foot. To be doing that at 16 in games, and with a lot of confidence, shows just how skilful he is. The stuff I've seen him do … there's no risk in having him in the NSW side."

That Pearce - the 19-year-old son of former Blues captain Wayne - is brimming with skill and confidence comes as no shock. But his Roosters captain and Blues teammate, Craig Fitzgibbon, revealed yesterday that NSW players had been gobsmacked by the skills the rookie exhibited in training.

"The players from other teams have mentioned they didn't realise how skilful he and [Roosters five-eighth] Braith Anasta were as a combination," Fitzgibbon said. "There's a bit of admiration for the boys. The others have known Braith for a long time but with Mitchell, they're a little bit taken aback by how advanced he is in his skill level and realising he's just a kid. And he's got so much more to offer."

They are reassuring words as concern mounts about NSW's ability to prevent another series defeat with a green halfback navigating the side. In fact, it doesn't seem long ago that Fitzgibbon was advising NSW selectors to overlook Pearce for the opening match, fearing he was too young and could be scarred by an Origin defeat.

Instead, selectors opted for another rookie in 22-year-old Broncos No.7 Peter Wallace, who was ruled out of the third match with a ruptured testicle.

Asked if he had changed his mind since the side went into camp about whether Pearce was too young to play a match of this gravity, Fitzgibbon said: "I have. Talking to him before it happened, and seeing where his head was at, he didn't think he was ready. Maybe now he's realised he is.

"I was just worried for him. But he keeps proving everyone wrong that he's ready for it. It's not the physical part of it but just the whole draining part of Origin. Look what happened after game two [when NSW lost 30-0]. Older blokes are a little bit more resilient to that stuff. You just wonder how much it might damage a young fella. He's 19, and a young 19. You just worry what could happen to that respect. But it doesn't seem to be daunting him at the moment."

While Pearce is playing in a decider, Mullen said the fact he was playing in Sydney - where the Maroons have won one from 13 matches, was a huge advantage.

"The thing for Mitchell is that it's down here," he said. "I had to make my debut up there in Queensland and it was tough. They were bagging me and death-riding me throughout the whole match."

There have been persistent rumours that Pearce would be benched and Knights utility Kurt Gidley would be promoted to the starting side but NSW coach Craig Bellamy ruled out that move "at this stage". Meanwhile, Fitzgibbon is approaching this rep match like it is his last but has kept the door open for possible inclusion in Australia's World Cup side.

"I don't think I have the right to retire from rep footy," said Fitzgibbon, who will finalise a one-year deal to stay with the Roosters after tonight's match. "I'm not that good a player. I have to go in there and do my best until I don't get picked again."

The NSW players received their jumpers from Blues greats Ricky Stuart and Paul Sironen at a function last night.