Saints coach Daniel Anderson sprung a major surprise earlier in the week by including the players in his initial 20-strong squad despite them nursing fractured cheekbones.
However, both men were omitted when Anderson whittled the squad down to 18 24 hours before kick-off.
Australian stand-off Jason Hooper keeps his place in the squad despite sustaining a dislocated shoulder in last Friday?s 19-16 defeat by Leeds.
Bradford are at full strength, with former Castleford prop Andy Lynch once more likely to miss out despite playing in all 28 matches of the regular season.
It means the odds are stacked against St Helens, who must avoid a third successive home defeat for the first time for eight years if they are not to make history by becoming the first team to finish top of the table and fail to reach the Super League Grand Final.
Paul Sculthorpe and Mark Edmondson are other absentees from a Saints side that lost 32-18 at home to the Bulls in the last match of the regular season just three weeks ago.
"Everyone has written us off in a little way," admitted Anderson. "We know we are in for a battle on Friday night but we?re not without a chance. We can play footie, we just need to take our opportunities when they come.
"You have to be prepared to go to lengths you haven?t been to before sometimes to win play-off games."
Saints last lost three successive home matches in the summer of 1997 when Australian clubs Adelaide Rams, Cronulla and Penrith Panthers all triumphed at Knowsley Road in the World Club Championship.
Home advantage could still be crucial if Anderson?s men are to set up a showdown with defending champions Leeds at Old Trafford on Saturday week.
"It will be disappointing if we don?t win a play-off game," conceded Anderson. "It?s desperation but it?s the same for both teams. We?ll get into the ring on Friday and see what happens."
If the former New Zealand national coach has adopted a siege mentality at Knowsley Road, the biggest task facing his opposite number at Odsal has been to keep his players? feet firmly on the ground.
Brian Noble has never failed to reach Old Trafford in his four years at the helm of the Bulls and, after an uncharacteristically slow start to the season, has brought his team to their peak at just the right time with 10 straight wins.
"We?re confident but I don?t think there is a favourites? tag in this game," he said.
"If you look at St Helens? record at Knowsley Road other than their last two games, it?s pretty impressive. They?ve had a little bit of disruption but these are one-off games."
Bradford, the champions in 2001 and 2003, have suffered plenty of heartache at the hands of St Helens over the years but they are at full strength and in form, having run up 115 points in their two play-off ties so far.
"We?ve been looking down the barrel of a gun for about seven weeks now," said Noble. "Our performances have improved and the team is confident. They?re used to pressure and they?re preparing very well. We?ve reminded them this week that it?s about their mental preparation."
The outcome could hinge on the ability of Saints to combat the threat of Lesley Vainikolo, who has scored 19 tries in his last eight matches since coming back from knee surgery while at the same time bringing their own Test star Jamie Lyon into the game at every opportunity.
Lyon managed to score two tries and set up another for his winger despite the wet conditions at Knowsley Road a week ago and could wreak havoc on a fast, firm surface.
"I hope it?s dry for the spectacle of the game," said Anderson. "Both teams want to play enterprising rugby league. Last week (Leeds coach) Tony Smith and myself didn?t go out to play rugby league, we went out to be conservative.
"Every team favours the top of the ground, no team likes playing in slosh."
St Helens 18-man squad: Wellens, Gardner, Lyon, Talau, Hooper, Fozzard, Cunningham, Gilmour, Wilkin, Higham, Bennett, Mason, P. Anderson, Hardman, Roby, Fa?asavalu, V. Anderson, Graham.
Bradford 18-man squad: Vainikolo, Deacon, Morley, Fielden, I. Harris, Withers, Johnson, Lynch, B. Harris, L. Pryce, Peacock, Paul, Vagana, Langley, Hape, Meyers, Radford, Henderson.
Referee: K KirkpatrickLike