There are few places in sport more scary than the UFC's Octagon.
Facing up to Australia fast bowler Mitchell Starc, maybe? Sitting in the quarterback pocket knowing a three-man blitz is on its way? They certainly can't be comforting scenarios, but for genuine primal fear, knowing the pain and injury one can suffer, the Octagon surely takes the cake.
So does the fear ever dissipate? Can a UFC combatant truly enter the ring comfortable with the potentially brutal beating he or she is about to take?
After 21 professional fights, fear remains a stark reality for Australia's biggest MMA star, and genuine middleweight contender, Robbie Whittaker.
"I think fear is completely normal, I think anyone who's about to fight a big, strong, scary dude, is [going to] feel fear and if you don't I don't think all your marbles are there," Whittaker told ESPN ahead of his UFC on Fox 24 showdown with Ronaldo Souza.
"But it's getting comfortable, it's getting in the rhythm, it's experience; I can just sum it up as experience. After you've done it a few times, the way you react under fear and under pressure and under nervousness is different, it's completely different to when you do it the first time. It never goes away, it never does. But you act and perform a little bit better each time."
Whittaker has come a long way from the 21-year-old Cityrail electrician who answered the casting call for the UFC reality show The Smashes that pitted a group or Australian and British fighters against each other, and had them live in the same house, way back in 2012.
Entering the contest with a 9-2 record across Australia's Cage Fighting Championship and the Legend Fighting Championships, Whittaker scored his biggest break when he took out the welterweight division of The Smashes -- even if it wasn't all cameras, bright lights and first-round TKOs.
"What I remember was that The Smashes was terrible," Whittaker told ESPN. "It was a terrible experience for me personally. A lot of the other boys liked it and had a lot of fun in there, but for me being away from my family for that amount of time and being stuck with all your enemies - it was a trying bit of life."
Whittaker admits The Smashes was in fact the launching pad for his assault on the UFC, but he says the building blocks of his success began long before even his first Cage Fighting bout.
"Yeah, I've got to give props to my dad. He got me into the UFC and the MMA scene to begin with.
"He instilled in me discipline, more than anything else. He told me and then outlined what I needed to do to get to where I wanted to be. There were a lot of times I wanted to quit, a lot of times when I wanted to go and play with my friends, and a lot of times I wanted to go act a fool, and he kept me on the straight and narrow, kept me on a good path and here I am today."
The other great influence on Whittaker's career is long-term coach Henrry Perez. The duo have been working together for well over a decade, with Perez juggling the responsibility of running his gym in south-west Sydney -- where he and Whittaker sat down with ESPN -- and then doubling down on training with his No. 1 student.
"Robert's work ethic has always been great," Perez told ESPN. "As athletes, we go through ups and downs and we've got to keep the consistency going. Even at the worst times we've got to continuously train and Robert has sustained that ability to move forward, not only physically but technically, and he's become more smart.
"With the support of the coaching system that we have now, his individual sectors of training have increased five-fold. He's doing great."
Twenty-two sectors of training to be exact.
"My standard training week, there's a lot of training in there," Whittaker told ESPN. "I have a high-performance coach who manages these spreadsheets of mine, manages my sessions and my loads. It's a very complicated process and he puts me through about 22 sessions a week.
"Basically I try to get across my striking, wrestling and grappling and jujitsu. Every day across the board I try to get an equal amount of sessions throughout the week because I need to improve in all aspects of my fighting. I fit those in somehow and I think I've hit a sweet-spot where I'm really enjoying the training and get great benefits."
But just as important as finding the physical "sweet-spot", and perhaps far more important when it comes to dealing with the "fear" element of UFC, is thorough mental preparation.
It will form a particularly crucial part of this weekend's UFC on Fox 24 bout against Souza, which takes place in the completely unfamiliar surroundings of Kansas City and carries the added hype of free-to-air television screening in the U.S.
"I think the mental preparation isn't something that you can work on in one large sum," Whittaker said. "It has to be a collective collaboration of doing little things for your mental state constantly throughout the prep, and managing your life outside the Octagon, managing your life in transit to the Octagon, managing your life once you get to training.
"It's a massive part of the mental systems that work for me, which ultimately lead to the mental systems leading into fight week and fighting."
From mental preparation and dealing with the fear, to the 22 sessions of training each week, Whittaker seems to have all bases covered ahead of his bout with Souza on Saturday [Sunday morning AEST].
All things going well it will be just another step on a journey that has taken him from the railways of Sydney, to reality television and, one day, the UFC middleweight title.
"It will mean everything, it will mean the result of a long, hard journey," Whittaker said when asked what the middleweight belt would mean.
"It will be the accumulation of efforts of not just myself, but of my family, of my friends, my coaching staff. And I think it's my duty and my responsibility to put everything I can into trying to achieve that goal because my friends and family share this dream with me."