NSW coach Laurie Daley says he’s done all he can to prepare new young forwards Josh Jackson and David Klemmer for the “unique beast” that is Origin.

But they won’t really know what’s coming until they’re thrown into the cauldron at ANZ Stadium on Wednesday night.

Jackson and Klemmer have been called into the Blues line-up to replace injured skipper Paul Gallen (hip) and Greg Bird (suspension) for the first game of their Origin shield defence.

Just two days out from the highly-anticipated encounter, Daley is hoping the debutant Bulldogs pair aren’t too overwrought at the prospect of facing a Queensland pack boasting Johnathan Thurston and Cooper Cronk.

“You can talk to them all you want about the pace of the game and how tough it is, but until they experience it they don’t really know,” Daley told reporters on Monday.

“I think they’ve just got to hit the ground running quickly and whatever happens, happens.

“They’ve just got to continue to work hard, work for their teammates and put their best foot forward.”

Back in Sydney and fresh from five days in camp at Coffs Harbour, Daley said he couldn’t fault the preparation of his young squad.

The defending series holders have had a far smoother lead-up this series than the Maroons, who’ve struggled with injuries to stars Billy Slater and Greg Inglis – both of whom have now been cleared to play.

The Blues coach admitted his debutants faced a big challenge in the unknown, but was comforted by the advantage of them being blooding at home in Sydney.

“It’s one of those things, you don’t really know,” Daley said.

“All you can go on is by the way they’ve trained, and you hope that they haven’t played their game before they get there.

“Origin is a unique beast, which they’re about to find out.”