After missing three games, the Warriors' star playmaker was back running the side at training on Thursday and testing his groin "every way possible" during a physical session.
Johnson suffered the injury before playing Manly in round 19 and re-aggravated it in a rushed attempt to return the following week.
Coach Andrew McFadden has named the 23-year-old Kiwis halfback as one of six changes to the starting lineup that scraped past NRL cellar dwellers Cronulla.
"In a pinch we could have played him last weekend," said McFadden, who later revealed that Johnson was not yet ready to be given the goal-kicking duties when they tackle the Knights at Hunter Stadium.
"He's done all the work, he's done all the rehab, ticked all the boxes. He's ready to go."
In another notable change, Kiwis utility Thomas Leuluai has been given the nod at hooker with defensive stalwart Nathan Friend dropping to the interchange bench.
Prop Ben Matulino, named to start outside Johnson in the second row, is set to bolster the right edge attack as the sixth-placed Warriors look to continue their climb up the NRL ladder in the final four rounds.
While injuries to Dane Nielsen (concussion) and Tuimoala Lolohea (hamstring) affected selections, McFadden admitted a number of players had paid the price for a scrappy performance against the Sharks.
He said the Warriors showed signs of complacency following their 54-18 thrashing of Canberra the previous week.
"Our attitude towards attack on the weekend was probably a result of the Canberra game. We just thought it might happen as easily," McFadden said.
"We didn't have the same detail around our game and it's something we've addressed."
With consecutive wins under their belt, the Warriors are faced with a third match-up against a team languishing at the foot of the ladder when they venture into Hunter Stadium.
But after the Knights pulled off a dramatic 32-30 upset over Melbourne in their previous outing, their position on the ladder is not an accurate reflection of their class.
