NRL.com understands that scans have cleared Gagai of a suspected broken hand, with the injury capping off a wretched Origin opener for the veteran centre in Townsville where a bout of tonsillitis severely hampered his preparation.
Gagai was placed on intravenous antibiotics leading into the Blues 50-6 flogging of Queensland and sat out South Sydney's win over Newcastle a few days later.
It's understood he has improved significantly on both health fronts since and is set to take his place against the Broncos on Thursday night, with Queensland's Origin II squad to be picked once round 15 wraps up next Sunday.
Arrow was the other Queenslander who struggled on Wednesday night, requiring a halftime painkilling injection to treat rib cartilage damage as he returned to the field.
The Rabbitohs and Maroons lock was also rested for Saturday's clash with Newcastle but is on target to play as well before Paul Green locks in his 17 for game two at Suncorp Stadium.
Storm and Maroons five-eighth Cameron Munster was placed on report for kicking out at Warriors captain Roger Tuivasa-Sheck on Sunday after copping a $1150 fine for a similar incident involving NSW rookie Liam Martin in Origin I.
Knights coach Adam O'Brien meanwhile indicated Queensland star Kalyn Ponga could "potentially" be among four Newcastle big names returning for his side against the Warriors next week.
Ponga was ruled out of Origin I due to an ongoing groin issue within 48 hours of being named for the series opener.
Canberra prop Josh Papalii returned from his own suspension in superb touch for the Raiders and offers considerable reinforcement up front as Queensland look to keep the series alive.
Maroons winger Xavier Coates was a pre-game withdrawal for the Broncos due to a hamstring twinge in the warm-up, though coach Kevin Walters said he expects him to be fit for the Rabbitohs clash as well.
"He's alright, he was a chance of playing but we thought it wasn't worth the risk with the short turn around for next week," Walters said.
"We expect him to be available for next Thursday. We'll see how he goes. He'll have some scans."