Walsh has been named as one of the biggest Origin bolters of all time, going from outside Brisbane's top squad at the start of the year to Queensland No.1 after seven games for the Warriors.

Fittler is the youngest player in NSW's State of Origin history, having made his debut just three months after his 18th birthday in 1990.

But he at least had marginally more experience to his name than Walsh, coming into the NSW side after 12 NRL games.

Walsh's call up makes him the second least experienced player in Origin history, behind Ben Ikin's famous "who-are-you" moment after four games in 1995.

While Ikin's selection came in the middle of the Super League war with Brisbane players unavailable, Walsh's shapes as a genuine Hail Mary play from a Maroons team in crisis.

"I know a few other blokes who have done that," Fittler said.

"It doesn't work out for everyone but I love watching him play, he's a real talent and we're going to have to be very careful.

"He brings a lot of footy to their team... He's a great footy player, very exciting.

"It seems he doesn't get discouraged by errors, just gets on with it. That's quite a trait."

NSW can, however, no doubt target Walsh at Suncorp Stadium, with his defensive readiness even questioned by Warriors coach Nathan Brown.

The youngster has missed 10 of the 22 tackles he's attempted in games he has started at fullback this year, and made five handling errors on Saturday.

While Fittler doesn't expect those issues to break Walsh on Sunday night, he is confident his Blues will have a plan to stop Queensland's X-factor sparking the Maroons.

"We're going the other way, we're going to try and dull it down," Fittler said.

"Our job is a bit different to their job so we'll worry about ours."

Australian Associated Press