Former baseball star Mike Piazza collapsed on the floor during a toxic tear gas training test that left him gasping for air on Wednesday's episode of Special Forces: World's Toughest Test on Fox.

Mike, 53, couldn't find the exit in the shipping container and dropped the medical bag he was sent to retrieve in a panic. When he finally made it outside, he was told that he failed.

'I fell down,' Mike said to the others. 'I feel like I've been slapped in the face by a thousand slaps.'

When the episode titled Resilience opened there were six recruits remaining on day seven of the experience. 

Carli Lloyd, 39, a former professional soccer player, worried about consistently not passing the instructor's tests.

'I just have to get my confidence up,' Carli said.

Remi Adeleke, a former Navy SEAL, told them they all had attributes that needed to be worked on.

'This phase is about resilience,' Remi said. 'We sweat more in training so we bleed less in combat.'

The medical officer told chief instructor Rudy Reyes that they thought they should remove former The Bachelorette star Hannah Brown, 27, from the gas drill because she had asthma and they could provoke a life threatening attack.

'We can test her in another way,' Rudy said.

Remi told the cast that chemical warfare was a real threat and that they needed to be prepared. Each of the recruits had to enter a container filled with poisonous tear gas and remove an object.

'Your bodies will tell you to run, but you must use your minds to block out every urge, block out the pain, and stand firm,' Remi said.

They each put on protective gear, but Hannah was told she would not do the competition.

'From a young age, I had asthma,' Hannah said in a confessional. 'If I can't breathe, I start panicking and then I think I'm going to die.'

Former NBA star Dwight Howard, 36, went first.

'You are about to have a taste of what it's like to invade Iraq,' Rudy said.

He instructed him to go inside the container and look for a medical bag and find another exit. Dwight put on his air mask. 

Once inside Mark 'Billy' Billingham, a former elite British Special Air Service member and one of the head instructors, instructed him to take off his mask and tell him his name and number. Dwight then grabbed the bag and found another exit and got out. He passed.

'It's burning like f***,' Dwight said of his eyes.

Danny Amendola, 36, Super Bowl champion, went after him. Danny completed the course quickly and successfully. Gus Kenworthy, 30, Olympic freestyle skier, located the bag and alternative exit fast as well and passed.

'That was the most painful s***,' Gus said.

Carli went last. She jumped out of the container without taking the bag with her and failed.

'I was right there,' Carli said. 'I dropped the bag.'

Remi said they were looking for people who could bounce back and learn from their failures. Back at camp they had Hannah jump in water and then roll in sand and pile sand bags in 105-degree heat.

Later, the instructors gathered to discuss everyone's performance. They called Carli to talk to her. They told her that she had failed the majority of tasks.

'I feel like I'm just trying to survive it,' Carli said.

Carli said she pushed her family out to focus on her training and she didn't feel anything, but that everyone suffered because of it.

'It was hard,' Carli said.

Carli said later she didn't want to fold under pressure. The instructors then had the recruits parade in their full gear. They took them for a run. Mike was struggling to keep up after the tear gas drill.

Remi told them they would be doing a task called 'milling' and two opponents would line up and fight each other.

'Even if the man or woman does go down you continue punching,' Remi said. 'You do not stop until I give you the command.'

Dwight and Danny fought each other wearing protective gear.

'I don't want to fight anyone because I don't want to get angry,' Dwight said. 'Times I have gotten angry I've done things I shouldn't have done. I feel fighting is not the answer.'

The fight was brutal. The instructors told them to continue to attack each other. They kept making them get up and punch each other. Danny was declared the winner.

Next, Hannah went up against Carli.

'I've never been in a fight,' Carli said in a confessional. 'I've never hit somebody. My pain tolerance is pretty high. I sort of have a sick obsession with the feeling of pain.'

The two punched each other in the body while the instructors screamed 'fight!' Carli overpowered Hannah and was declared the winner. The two hugged after.

Mike and Gus were the last to fight.

'I've been in fist fights before but you have to have a strategy,' Mike said in a confessional.

Mike got knocked to the ground and Gus punched him in the stomach. Mike got up and punched Gus back. Mike bent over and the instructors told him to stop. Gus was declared the winner and they hugged.

'This was a tough day,' Mike said.

Later, Mike said he was considering quitting.

'It's a young man's game,' Mike said.

The instructors brought in Mike to talk to him. They told him he was the oldest recruit left and Mike said he would think of his children for motivation.

'I will press forward and try to dig down deeper,' Mike said.

At night, they got everyone up and told them they were becoming better versions of themselves. Then the instructors brought Mike up and because he didn't have his armband on made all the other recruits do push ups.

'These guys never let up,' Mike said.

Mike later sat by himself while the others were inside.

Special Forces: World's Toughest Test will return next Wednesday on Fox.