"I wouldn't be in this situation if I didn't think I was [going to be fit] for Sunday, it's all going well so far," Slater told media on Wednesday.
"I understand what it takes to play a game in an Origin, I'm pretty confident I'll be right on Sunday."
Slater is set to play his 30th State of Origin match when Queensland face New South Wales on Sunday with the Blues looking to lock up a series win at home following a 22-12 victory in Melbourne in game one.
"We've got a challenge in front of us, we've got to go down to Sydney, it won't be easy," he said.
