It's undoubtedly a difficult position to be in, and there were far more experienced players who were just as poor when the change was made – but Ilias took the bullet.
It was always going to be a difficult task for the 23-year-old to replace not only a club legend, but a club legend who came into first grade as a rookie in 2012 and immediately succeeded, steering the Bunnies to a top-four finish.
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Adam Reynolds' ability to do that was an outlier, and one that shouldn't be used as a stick to beat Ilias with.
If you look at some of the other great halfbacks of the past two decades; Cooper Cronk was used as a bench option or a No.6 outside Matt Orford in his first two years with the Storm, Nathan Cleary's Panthers were mid-table in his first few campaigns, and Johnathan Thurston was firmly behind Brent Sherwin and Braith Anasta in the Bulldogs' pecking order before moving to the Cowboys in his fourth NRL season.
That's not to compare Ilias to these players, which would be ridiculous – and it's clear from Souths' mediocre attack despite a glut of attacking chances in most of their games, that he and other key men haven't played well enough.
It's simply to highlight that the ability to be thrown in the deep end in such a key position – and still thrive – is uniquely tough.
Daly Cherry-Evans, who won a grand final in his rookie year, and Reynolds himself, are rare exceptions.
It's also worth remembering that this wasn't Souths' original post-Reynolds plan. Anthony Milford had been signed and was likely to be the first choice No.7, when off-field issues complicated matters.
It's hyperbolic to say that Ilias' career is at a crossroads but how he bounces back from this is pivotal – there's every chance he's playing NSW Cup in a fortnight's time if Souths opt for Kodi Nikorima to partner Cody Walker in the halves, as Latrell Mitchell returns to fullback.
Jason Demetriou saw something wasn't working and made an adjustment to try and win the football game. Souths were still flogged, but you can't deny the decision was effective – it was 32-0 against them before the change, and 12-0 in their favour afterwards.
Had Damien Cook not thrown an intercept to Ben Hunt on the goal line, it would likely have been 32-18 with about 20 minutes to go, and a few nervous types in Red V shirts looking around.
A lot of people were critical of the decision due to how it might stunt Ilias' development – but however futile the situation, Souths were still trying to make decisions that would help them win – and it's worked for teams in big games before.
Chad Townsend was famously hooked during a 2016 finals game for Cronulla, in a match they would eventually win over the Raiders.
"I was devastated to be honest," the halfback told AAP the following year.
"The day after, you sort of start to question what was it? Was it your preparation, was your head not on?
"Things weren't going my way then and my character was getting tested. I had to think about how can I show up and show I'm worthy of being here?"
Ilias could learn a lesson from the veteran, who took the benching in his stride and bounced back to play a brilliant role in a preliminary final win over the Cowboys, and then won a premiership nine days after that.
"What's done is done. I can't change what's happened in the past," Townsend said.
"But what I could do was just knuckle down and turn up to training on Monday with my chest out and just control what I can control."
Souths' team culture is very good and there's no doubt that Ilias will have a large support network, should he be left out of the team against Parramatta.
After that, what happens next is up to him.
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