While Saints have a clean bill of health, the Giants have lingering injury doubts over stand-off Thorman, who pulled a hamstring against Hull FC eight days ago and first-choice wingers Stuart Donlan (quad strain) and Martin Aspinwall (groin).
Hooker Brad Drew, Huddersfield?s vice-captain who will lead the team out if Thorman is missing, is expected to recover from a calf strain and full-back Paul Reilly has shaken off a neck injury that forced him to sit out last Friday?s defeat at Wigan Warriors.
Coach Jon Sharp is likely to leave it until an hour before kick-off before announcing his team, even though he has to name an 18-man squad on Friday when the team hold their traditional walk-about on the Twickenham pitch.
Sharp admitted today that Thorman remained "extremely doubtful" and the player revealed at the club?s media day that he will have a fitness test on the pitch at Twickenham.
"You can?t strain it, you can?t go 100%, and I?m not going to risk it before Saturday," said Thorman.
"It?s only going to be me that knows if I?m able to play.
"We?re trying an alternative therapy. We?re going to see how it responds to acupuncture. I?m going to see our physio Gary Slade?s wife, who is a trained acupuncturist."
Thorman, who missed the fifth and sixth-round ties of the Cup with a broken thumb, insisted that he would not play at Twickenham unless he was fully fit, pointing to the example of Leeds Rhinos centre Keith Senior who limped out of last year?s final at half-time after failing to shake off an ankle strain.
"Absolutely not," he said. "That?s a prime example. He probably shouldn?t have been risked. It?s a good one to see what could happen if you go into the game sort of half-hearted or 75% fit.
"It?s not something I want to do. I don?t want to hinder the team?s performance in any way.
"It would be very special to lead the team out and I?m just basically keeping my fingers crossed. I would love to be a part of it.
"I?ve said since I got back from Australia that the squad that Jon has assembled is capable of whatever they want to be.
"I think they can go a long way in the game, starting on Saturday and for me not to be a part of that would be a massive disappointment."
Sharp is set to name all his injured players in a 20-man squad on Tuesday but admits he will not be in a position to name his line-up until later in the week.
"At this stage, Chris is looking extremely doubtful," he said. "We?re not ruling him out just yet but obviously it is a race against time.
"He?s a very special player to us. He is our captain, a fantastic leader, and he has a big part to play in the things that we do.
"It will also be a late call on Brad Drew, who is improving. We wrapped him in cotton wool last week and we?re going to try to get him moving this week.
"Martin Aspinwall broke down in practice last Thursday with a groin strain but hopefully over the next two days he?ll be able to start taking part in practice."
Huddersfield are also without utility back Kevin Brown, who deputised at stand-off against Wigan on Friday but is cup-tied, and Sharp admits he may be forced to turn to teenager Tom Hemingway, who made his first start of 2006 against the Warriors.
"He was fantastic against Wigan," said Sharp. "He?s been extremely good in every Super League game he?s played in.
"He looks really comfortable on that stage and I wouldn?t have issues whatsoever in playing Tom Hemingway."
Huddersfield Giants 20-man squad: Reilly, Aspinwall, De Vere, Donlan, Thorman, Paul, Crabtree, Drew, Gannon, Nero, Snitch, Wild, Jones, Jackson, Smith, McDonald, Raleigh, Gardner, Hemingway, Mason.
Referee: R Silverwood