Trbojevic looked set to be picked for the May 31 match in Adelaide before reporting calf soreness in his NRL comeback game on Sunday afternoon.
That prompted a last-minute change of plan for NSW coach Brad Fittler, calling Pangai into the squad as one of three debutants alongside Cronulla's Nicho Hynes and Canberra's Hudson Young.
Pangai will start in the front row alongside Payne Haas, with Junior Paulo to come off the bench.
Fellow debutant Young will also start in the second row on one edge with the recalled Tyson Frizell on the other, bumping Liam Martin and Cameron Murray back to the bench.
"Jake was pencilled in," Blues assistant coach Greg Alexander told SEN.
"As you know you can't pen anything in until everything's over and we got word that Jake had re-injured that calf, which was disappointing after coming back and making his return against Canberra."
Fittler has stuck with Jarome Luai and Nathan Cleary in the halves, and made the bold call to leave Damien Cook out of the squad for the first time in his tenure.
Apisai Koroisau will act as the sole hooker, leaving room for Hynes to debut off the bench and playing some dummy-half if required.
Cook was expected to win the No.9 jersey and add to his 15 consecutive Origin games before Koroisau's Saturday night performance for Wests Tigers got him over the line.
Koroisau's combination with Luai, Cleary and lock Isaah Yeo from his three years at Penrith is also viewed as a key advantage for the Blues.
"Damien Cook has played good," Alexander said. "We didn't think the two hooker situation worked for us and we've tried it a number of times.
"We just thought we'd go with one hooker and Api gets the nod.
"Api's ability out of dummy half to not just play off the back of a quick play-the-ball, probably got him the nod. The fact that Api can play off the back foot."
Tom Trbojevic and Josh Addo-Carr were selected at centre and wing respectively, with Campbell Graham initially picked as 18th man before withdrawing with a sternum injury.
Penrith centre Stephen Crichton will take his spot as the concussion substitute.
There had been concerns over both Trbojevic and Addo-Carr's fitness, but Trbojevic blew those away with a hat-trick of tries against Canberra on Sunday.
Addo-Carr also came through his return game for Canterbury unscathed, five weeks after syndesmosis surgery.
Sydney Roosters second-rower Angus Crichton and Bulldogs centre-turned-half Matt Burton are among players to miss out after playing Game III last year.
NSW:
James Tedesco, Brian To'o, Latrell Mitchell, Tom Trbojevic, Josh Addo-Carr, Jarome Luai, Nathan Cleary, Tevita Pangai, Apisai Koroisau, Payne Haas, Tyson Frizell, Hudson Young, Isaah Yeo. Bench: Junior Paulo, Cameron Murray, Liam Martin, Nicho Hynes. 18th man: Stephen Crichton