Teenager Cory Aston looks set to feature should Walker be sidelined, while Halifax will assess Anthony Thackery (ankle) before finalising their team.
Halifax won 40-18 against Workington Town last week, but coach Karl Harrison is demanding improvements.
Harrison said: “At times we played really, really well, but then we’d drop off a little bit. There’s still a lot to work at going into the play-offs, but we go in there with a lot of confidence.”
He added: “It’s always a tough game at Sheffield and we’ll be preparing for a tough game.
“When it comes to the play-offs you just need a little bit extra, and hopefully this season we will have that.”