Robinson on Wednesday revealed Walker had shocked the Roosters just days after undergoing ankle surgery by targeting week three of the finals for his return date.
"He's 100 per cent," the coach said on Wednesday.
"Two weeks ago, I said, 'Do you think you'll be right for the last game of the year?' and he said, 'I'll be right for the one before that'. So even that surprised me: the physical capacity and treatment he's done to have the mindset to get back ready to play."
"He's done more than enough. He's moved in lots of directions so far so, yep, ready to play. I wouldn't put him in if I didn't believe in him and I didn't believe in his capacity to play a finals game."
No half measures, Walker will be expected to play 80 minutes and take over the goal kicking from Hugo Savala, who has been relegated to the six-man bench for the Queensland Origin star's return.
But Robinson is promising to use Savala in some way after the 24-year-old deputised so capably at five-eighth in Walker's absence over the past three weeks.
"Hugo is so important to our team and the way that he approaches the game and plays the game and he'll have his part to play," the coach said.
"He's earned his right to continue to play and he'll get that."
Robinson, though, never considered starting Savala in the centres at Billy Smith's expense.
"Billy's our left centre. He always has been," he said.
"I know there's been some discussion, but there hasn't been discussion inside these walls around that.
"We know the value Hugo can play and he will do that, but Billy's our definite left centre."
While Walker's comeback dominates the headlines, the Roosters are playing down any concerns over the health and fitness of fellow linchpins James Tedesco and Daly Cherry Evans.
The skipper and halfback both sat out training on Monday with illness.
"A little bit crook, but that's cool. That's the life of an athlete," Robinson said.
"There's always either injuries or illness or babies or moving or whatever you want to throw up and a bit of our mantra is we'll care about you Monday to Friday but game day we don't care: get ready to play.
"Yeah, they're pretty good. Daly should get through a fair bit. James will get through a bit today as well."
