Game of Thrones star Hafþór Björnsson, who played Gregor "The Mountain" Clegane on the HBO drama, showed off his incredible physique ahead of his boxing match against Devon "No Limits" Larratt on Sept. 18.

Björnsson weighed in at 146.5 kilograms (322.9 lbs.) on Sept. 17. Originally, he was scheduled to fight fellow strongman Eddie "The Beast" Hall, but Hall suffered a bicep injury and the aptly titled "Heaviest Boxing Match in History" was postponed to 2022.

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Outside of his work on Game of Thrones, the 6-foot-9 Björnsson is an accomplished strongman competitor and has won the Arnold Strongman Classic, Europe's Strongest Man and even the coveted World's Strongest Man competition. In May 2020, he also set a new world record by deadlifting 501 kilograms (1,105 pounds), though this was done in his home gym and not in an official competition. The previous record-holder was the aforementioned Eddie Hall, a former World's Strongest Man in his own right.

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While Björnsson weighed over 450 pounds when he accomplished that feat, he quickly began shedding weight while pursuing boxing. His first exhibition match took place in January 2021 when he competed against the 217-pound Steven Ward. At the time, he weighed 344 pounds and was declared "The first TITAN WEIGHT fighter in history."

"I’ve been in Dubai for almost five weeks now ahead of my fight on September 18th," Björnsson recently told Muscle and Health. "This will be my third official fight in preparation for my main opponent and the very reason I started this boxing journey- Eddie Hall. When Eddie announced he’d torn his bicep and we had to postpone the fight until 2022, of course, I was disappointed. I’ve been training so hard for that specific fight, but there’s nothing we can do, he’s injured, so we had to move forward and reschedule."

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Regarding his diet, Björnsson noted how he's gone from eating roughly 10,000 calories a day when he was competing as a strongman to consuming about 75% less food. "I would eat so many calories to try and gain weight that often I would eat and then literally fall asleep on the table," he said. "I would just pass out. I was just that exhausted from eating and training. Of course, having transitioned to boxing, my diet has changed a lot. I’m eating a lot less, very clean."

Source: InstagramMuscle and Health