The 13-year-old boy, already sedated in preparation for his dangerous extraction from the Thai cave that had imprisoned him and 12 others, had already been sedated in preparation for the perilous journey out of the cave.
That’s when Mallinson released that the breathing mask was too big for the young boy’s face.
“We put it on him, really strapped down tight so his nose was flattened against his face and there was a big gap under his chin. We just couldn’t get it to seal,’ Mr Mallinson told ABC’s 20/20.
Without a seal, Mr Mallinson knew the boy would drown.
A team of more than 150 worked together to free the group from Tham Luang cave, a 10-kilometre long limestone cave system.
With no way to contact rescuers at the cave entrance, Mallinson knew there was no way they would be able to get a smaller mask.
“We knew we didn’t have any more time and we knew this was the last option,” Mr Mallinson told 20/20.
“Once you set off with that kid, it was a one-way journey. You weren’t going back to where they started. … It was a case of getting him out. A bit brutal … but dead or alive.”
“It was so nervous for me because it was the different type of mask with this seal that you could dislodge sideway. I had to be so careful with him,” he said.