Kalyn Ponga's early exit from camp Maroon has left Queensland coach Paul Green with little room to move as he waits on a host of others to prove their fitness for next Wednesday's State or Origin opener.
Ponga will return to Newcastle to rehabilitate a groin complaint that has kept him out of NRL action since May 8.
Maroons medical staff ruled him out on Wednesday, a day before the team's first official training session as Green attempts to settle on a side by the end of the week.
Valentine Holmes is Ponga's likely replacement in the No.1 jersey with the winger's move infield clearing the way for North Queensland clubmate Kyle Feldt to debut at his Townsville home next week.
AJ Brimson, who capably replaced Ponga for the series opener last year before he too was injured, is another option at fullback.
But he has been slated as Green's bench utility and is himself nursing a sore knee, aggravated on Sunday while playing for the Gold Coast.
Most pressing will be the fitness of five-eighth and last year's player of the series Cameron Munster (foot), who has also been out since May 8 and only late last week returned to running.
Ponga was an option to replace Munster in the No.6 but if both are unfit to play it could force Brimson into the halves.
Brimson is open to anything but it would be a drastic move Green hopes to avoid in his maiden Origin campaign.
"Anything can happen, so I'm ready to go wherever," Brimson told AAP.
"If he (Green) wants me on the bench, if he wants me starting, if he wants me to be 18th man, if he wants me front-row, it doesn't bother me.
"I'll take it off the kick-off, I don't mind."
Knights coach Adam O'Brien had given Ponga his blessings to enter camp, but did so with a high degree of caution as he stressed an early return could lead to "a really serious injury".
It means Ponga has played just three of a possible nine Origins since his remarkable debut off the bench in game two of the 2018 series.
A hamstring injury kept him out of the third game of that campaign, before a calf complaint ruled him out of the 2019 decider.
Ponga then opted for end-of-season shoulder surgery last year, ruling him out of the entire 2020 series.
Hooker Harry Grant and Melbourne teammate Christian Welch also missed recent games with niggles but have indicated they will be fit to play, while Storm backrower Felise Kaufusi will play his 10th Origin game after successfully challenging a tripping charge at the judiciary.
Tickets for the historic Townsville instantly sold out on Wednesday, many Townsville locals earlier left stranded lining the footpath attempting to secure them in person.
Capacity at the new Queensland Country Bank Stadium is set to be increased by about 2000 to ensure more than 30,000 fill the stands.