The Queensland camp is increasingly confident of having playmaker Cooper Cronk on deck for Wednesday night’s State of Origin series opener against NSW in Sydney.

Coach Kevin Walters will trust Cronk with the final call on his fitness – not doctors – as the influential No.7 battles an ankle injury suffered at training on Friday.

Queensland’s only series defeat in the past decade came after Cronk broke his arm early in game one of 2014, but the Maroons are optimistic their halfback general will play after completing most of Tuesday’s captain’s run at ANZ Stadium.

Lock Corey Parker says much will depend on how Cronk pulls up on match day.

“The final call will be on ‘Coops’. He won’t go into a game jeopardising his position in the side,” Parker said on Fox Sports’ NRL 360.

“Look, it looked promising (on Tuesday) and, for his sake and for Queensland’s sake, I hope he does take the field.”

Walters, though, won’t take any risks if Cronk isn’t feeling 100 per cent confident of surviving 80 minutes in the Origin cauldron.

“In the past, we have taken players who are not quite 100 per cent and it has fallen apart,” said the first-year Queensland coach.

“We don’t want to fall into that trap.

“The swelling has gone down but these injuries take time to heal.

“He only had four days. It’s remarkable to get to this position but there won’t be any risks taken.”

Parker admitted Cronk would be tough to replace but backed Michael Morgan as more than capable of filling the void.

Morgan will start at five-eighth, with Johnathan Thurston moving to halfback if Cronk is ruled out and the Maroons are backing the North Queensland premiership-winning playmakers to get the job done if that’s the case.

“He’s a really structured player, `Coops’, and he’s an integral part of our team. He has been for a long period of time,” Parker said.

“His direction around the field is second to none.

“But if he doesn’t take the field, his replacement’s got a pretty good combination with ‘Thursto’.

“They combine quite well and have done for a number of years.

“But I think ‘Coops’ might be in a position where he does take the field.

“If he doesn’t, I’m sure `Morgs’ will do a fine job.”

If Cronk is scratched, Warriors forward Jacob Lillyman will be promoted the 17-man squad, giving Queensland four forwards on the bench.