The NRL’s investigation into Eliesa Katoa’s concussions while playing for Tonga on Sunday will reportedly focus on how the warm-up incident wasn’t picked up.

Host broadcasters showed after-the-fact footage of Katoa being hit with shoulder-to-head contact during the warm-up.

The second-rower, who is one of the best in the game, would then go on to have two more head knocks in the game before being withdrawn from the contest.

Alarming scenes would follow as he required oxygen before being taken to the hospital, where he remains in a stable condition, having had surgery for a bleed on the brain.

There has been speculation that the forward could be forced to retire, although no official comment has been made to that extent yet, after the alarming circumstances.

While the NRL are well set up to ensure all concussions are picked up, and possible ones are tested, during the course of a game, that is not the case in warm-ups, where broadcasters aren’t filming the teams from every angle.

Instead, it’s on the clubs, or in this case national staff, to pick up incidents.

The Katoa pre-game incident was evidently missed, and News Corp is reporting that, while the investigation will not be rushed out of respect for Katoa, his family, the Storm and the game in general, that is where they will be focusing their energies.

It’s unclear if the game could bring in new policies around warm-ups for head knocks, with concussions becoming an ever-increasing issue for the NRL in every element of the sport, from training to games.

While the NRL will ponder what the next steps are in that space, fears for Katoa will continue, with former New Zealand international Shaun Johnson calling for heads to roll.

“I feel a bit angry about the situation,” he said on the Play on Sport Show.

“I don’t get how it can even get to that point, but from a player’s view, we just hope that Eli’s all good. Anyone that’s been in that situation or has seen teammates in that situation, it’s the worst thing to see.

“I’m just going to say it – there is going to be fallout over this. There are going to be some heads that are rolled because I do not know how Eli Katoa was allowed to take the field.

“In warm-up, he has a shoulder to the head…loose body to the ground. All I thought straight away when I saw that was if that happened in a game or if that happened at training during the week, he’s done, and they’d probably go category one on it, so he wouldn’t even sit an HIA and would be done.”