The NSW Blues have already been confirmed to lose Nathan Cleary and Apisai Koroisau for Game 2, but that list could grow in size before the team is confirmed by coach Brad Fittler on Tuesday morning.
All of Liam Martin, Cameron Murray and Latrell Mitchell are racing the clock to line up for the second game of the series.
Martin is the latest blow for the Blues, suffering a concussion during Saturday evening's win for the Penrith Panthers over the Sydney Roosters at Allianz Stadium.
He was ruled by the NRL bunker's independent doctor and was promptly ruled out of the remainder of Saturday evening's game, while a possible 11-day stand-down accompanied the decision.
Origin 2 in Brisbane - to be played on Wednesday, June 21 - was exactly 11 days after the incident, and Fittler hasn't ruled out a possible return, with Martin qualifying under the NRL's new blanket concussion rules for a possible early return, as we have seen for Tom Trbojevic and Reed Mahoney this weekend.
Fittler said on Channel 9s The Sunday Footy Show that it would come down to passing a test two days after the incident - on Monday - to ensure Martin was any chance of playing.
“The key is that he sees the CMO at Penrith after two days, 48 hours. That's the important test they have to pass to make sure they haven't got headaches from the incident,” Fittler said on The Sunday Footy Show.
“I spoke to Liam this morning, he was OK after the game. Hopefully, he gets through that. Time wise he gets through the protocols to play. There are things to do with contact at training and certain things they can do at training so that will all be supervised.”
Mitchell and Murray are equally as uncertain to play.
The star fullback Mitchell, who played centre for the Blues two years ago, but missed the entirety of last year's series, was a late withdrawal from Game 1 in Melbourne with a calf injury. It was anticipated he would have returned on Saturday against the St George Illawarra Dragons, however, failed to pass as fit for the game.
Murray, on the other hand, revealed he had suffered what he believed to be tightness before increasing the level of a groin injury in backing up from Game 1 against the Gold Coast Titans.
He too missed the game against the Dragons on Saturday at Kogarah, with South Sydney lost 36 points to 30.
Fittler said a decision on the duo will be made on Monday, while it's believed Cody Walker's chance of playing Game 2 went up in smoke with a groin injury of his own that forced him to miss Saturday's game.
“They ran (on Saturday). I spoke to (Rabbitohs physiotherapist) Eddie Farah (on Saturday), they have been really open with their communication. They have a few players injured so they all ran to a degree and they will all run tomorrow (Monday),” Fittler said
“We'll liaise with them and see how they are. There is a physical side and there is a mental side as well.
“Getting up for State of Origin is a big ask. You need to be going with your whole body.”
Origin 2 will be played on Wednesday, June 21 in Brisbane, with the Blues to confirm their team on Tuesday following the completion of the currently ongoing Round 15 in the premiership.