NSW winger Brian To'o is on track to overcome a hamstring issue and play in State of Origin II, but Jacob Kiraz remains on stand-by for a whirlwind debut.
Coach Laurie Daley said he and his staff would make the final call on To'o's fitness after the Blues' final training session in Sydney on Saturday.
The team flies out to Perth the next day with the hopes of sealing a series victory over Queensland.
To'o pulled up sore after Penrith's defeat of Wests Tigers on Sunday and did not train with the team during Thursday's session in the Blue Mountains.
The Blues are taking a cautious approach to To'o's fitness given two previous hamstring issues earlier this season, but are confident he will line up on the left wing at Optus Stadium.
"He trained as well as what we wanted him today so he's on the right path," Daley said.
"He'll be okay, if anything changes, it would be on Saturday because you want to make sure he has a really good hitout. But I don't think he's in any doubt."
Kiraz was called in to train with the Blues on Thursday in To'o's absence, despite outside backs Tom Jenkins and Kotoni Staggs already being in the wider squad.
In the event To'o is deemed unfit for Origin II, Daley confirmed Canterbury winger Kiraz would be rewarded for a fantastic season with a maiden Origin cap.
"Most definitely," the coach said.
"We'll make a decision one way or the other on Saturday."
The Blues have already been granted an exemption to bring Jarome Luai into the team from outside the squad Daley initially named, with Mitch Moses now unavailable through a calf injury.
They would need to apply for a second exemption if To'o is also deemed unfit.
But the NRL is typically more lenient in granting such exemptions for Origin, given teams name only a 20-player squad rather than the 22-players for club games.
There is also a sense the best teams possible should be available for Origin.
The opposition is unable to challenge or query a team's request for an exemption, with the NRL assessing each injury on a case-by-case basis before having the final say.
Kiraz will not be available for the Blues' training session on Saturday given the Bulldogs face South Sydney the next day.
