USA Today

UFC featherweight title contender Conor McGregor is walking into the fight of his life at UFC 189. As MMA fans know, however, a big fight is almost certainly preceded by a big weight cut. Former three-time UFC title contender and fellow weight-cutting champ Chael Sonnen recently appeared on The Jim Rome Show to discuss McGregor's weight cut and his matchup with Chad Mendes.

"He's a very big guy. I was impressed with how big he is," Sonnen said (h/t LowkickMMA.com for the transcription). "I was like, 'Conor, what do you weigh?' He said, 'I'm around 172 pounds.' He's got to be 145 pounds in eight days."

Extreme weight cutting is a common practice in most combat sports, with athletes often shedding dozens of pounds over the course of a few weeks in order to make rigid weight limits. Fighters requiring hospitalization (like Kelvin Gastelum or Henry Cejudo) or even dying (like Leandro Souza) is not unheard of, as they subsist on meager rations and spend hours each day in saunas or on stationary bicycles.

Absurd anecdotes and alarming statistics are the norm for MMA. Chael Sonnen lost 20 pounds in under 24 hours ahead of his UFC 148 rematch with Anderson Silva. Paul Redmond was tasked with losing 36 pounds in 13 days for a short-notice bout at UFC on Fox 14. Ian McCall once weighed in at 125 pounds in the afternoon and over 150 before going to bed.

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For McGregor—and almost any other fighter—those weight cuts can translate into a huge size advantage in the cage, which allows the Irish southpaw to snipe opponents with rangy punches. Against Mendes, who competed at 125 pounds for part of his collegiate wrestling career, McGregor will own a whopping 8-inch reach advantage, which could be a difference-maker in the striking and grappling departments.

Dropping 27 pounds within a matter of days may seem like an impossibly tall order, but McGregor has dropped down to "championship weight" in the past, making the firm 145-pound weight limit that featherweight title fights require. He boasted about doing so at his most recent fight against Dennis Siver in January, saying at UFC Fight Night 59 weigh-ins, "That's 1-4-5, that's championship weight. Tell Jose [Aldo] I'm coming."

McGregor faces Mendes on July 11 and will weigh in Friday. Circle back to Bleacher Report for our coverage of the event as it unfolds.