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Max Holloway earned respect from MMA fans for having the moxy to accept a UFC 223 fight against lightweight contender Khabib Nurmagomedov on short notice after Tony Ferguson withdrew from Saturday night's event in Brooklyn, New York, with a knee injury.

Anyone who's paid close attention to the sport over the years, however, knows the toughest, oftentimes most dangerous part of fighting isn't the wrestling and punching in the cage. It's the grueling weight cut beforehand.

Judging from Holloway's nutritionist George Lockhart's comments to BloodyElbow.com, the trek down to 155 pounds might be even scarier than a match with the grappling specialist, considering he was given a six-day window in which to do it. The weigh-in for the fight will take place Friday morning.

IG Caption: Khabib, far left, and Max, far right, cutting weight for their fight in close proximity.

"Yeah, this is literally tied with the biggest cut I've ever done. It's the exact same number as the biggest cut that I've ever done in my life," he said. "We usually want to start 10 days out. ... When most people we're working with come to fight week, they've already done the weight loss and it's time to just drop the water. With Max ... we're going to have to get a little fat off, though he's already pretty lean right now."

Weight cutting is a practice in combat sports where competitors lose weight to compete in lighter divisions. How it happens and the extremes athletes go to vary from sport to sport. But in MMA, fighters routinely lose tens of pounds through dehydration and extreme dieting. Naturally, this can result in any number of issues, ranging from diminished in-competition performance to long-term bodily damage to death.

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There is no specific number of pounds Holloway needs to lose by Friday's weigh-in (Ariel Helwani was vague, mentioning on Monday's The MMA Hour that the fighter is under 200), but there is no question Holloway is in for a tough ride. However, Lockhart seemed confident he will be able to make weight.

"We talked about how he's feeling, and he can do the road work and all the aerobic activities he needs to do in order to burn the fat he needs to burn," he said. He continued later, saying, "He's going to get off the plane, put his shorts on and start running. I know he's got the right mindset. Max is the one guy that can do that."

To compete for the UFC lightweight title, Holloway will need to step on the scale at or under 155 pounds Friday morning. Hopefully he can do so safely, because a contest with one of the UFC's scariest competitors awaits.