Olympian Melissa Wu collapses in terrifying scene on SAS Australia

Viewers were confronted with shocking scenes on SAS Australia last night after a lifeless-looking Melissa Wu collapsed face first.

The reason for Melissa Wu’s terrifying collapse on SAS Australia has been revealed after viewers were confronted with the shocking scene in the most recent episode of the Channel 7 show.

Trailers had long teased the scary moment and on Tuesday night the challenge that led to the Olympic diver falling face-first to the ground was shown in full.

Contestants were forced to go into a shed-like structure filled with tear gas and attempt to rescue “hostages” trapped inside by cutting their chains with boltcutters.

Wu — a two-time Olympic medallist who won bronze in the 10m platform event in Tokyo — started to struggle when her gas mask was removed by an instructor after entering the shed.

She had to leave before cutting the hostages free and stumbled outside then collapsed to the grass.

She was motionless as instructor Ant Middleton lifted her up, looked at her eyes glazed over, then laid Wu on her back as he tried to get more oxygen into her.

Other contestants looked on in horror, Locky Gilbert saying “oh s**t” when he saw what was happening, as a doctor was called to help. An oxygen mask was put on Wu’s face and she soon regained consciousness.

“I came out of the room, and then I don’t remember after that,” she said.

Middleton said the reaction to being exposed to tear gas is like “you’re on fire from the inside out”.

“Tear gas shuts down the body the moment you take that first breath in, your body closes up, you’re completely disabled, it’s horrible,” he said.

After the challenge was filmed, Middleton opened up on the troubling incident as he explained what happened and why he reacted the way he did.

“First of all, I wanted to see if there was any facial damage, any teeth inverted, a broken nose, blood,” he told 7Entertainment.

“I knew what it was, I knew it was a lack of oxygen. So I went over those visuals of her face and airways and laid her down so the blood circulated to her head.

“They (some soldiers) come out of that environment, it has a — I wouldn’t say devastating — but it has a different effect on their body, and they pass out.

“But they come back very quickly, they just need to get oxygen to the body.

“It was an effect that I’ve seen before, but one I wasn’t expecting.”

Melissa Wu is an Olympic veteran. (Photo by Clive Rose/Getty Images)