Assistant coach Matthew Primus all-but confirmed on Wednesday that giant-ruckman Smith would return direct to the seniors after 12 months out with a ruptured ACL.
Primus said although the final decision would be left until Thursday's match committee, Smith was right to go.
"Zac's done a power of work," Primus said.
"We understand he's not going to be at his best, but whatever level he plays at, we just want him to compete in the ruck as he does and his touch will come through."
The usual protocol would be for Smith to return through the reserves, but he was put on the long-term injury list at the start of the season to undergo extra conditioning and not rush back.
With fellow ruckmen Tom Nicholls (PCL) and Dan Gorringe (Achilles) both unavailable, Smith would make his return on the one-year anniversary of his injury.
He said despite doing what felt like "two pre-seasons" that included tackling, being tackled, and centre square jumping, he would be nervous at the weekend.
"It's exciting. It's been a long journey," Smith said.
"I haven't played the game in 12 months and I'll be pretty nervous on how I perform."
Smith, 24, said watching his teammates rush to a 5-2 win-loss record and into sixth place was exciting.
"To see how the boys have grown over pre-season and how they've performed at the start of this year, I'm itching to get back into the side to give myself to the team and play my part in to that success," he said.
Primus said he would much prefer a genuine ruckman to the alternatives of using Charlie Dixon or Rory Thompson in the role.
"It's also good for our key forwards and backs to be able to cement themselves down there," he said.
"It's a difficult ask to play in the ruck then go forward or go back.
"Traditionally we'd like a dominant ruckman, then somebody to chop them out for five to six minutes a quarter."
