Hafþór Björnsson, known to Game of Thrones fans as the second actor to play Gregor "The Mountain" Clegane, has made boxing history by becoming the first titan weight competitor.

"The first TITAN WEIGHT fighter in history, ready to take on this new challenge. I’m excited, and I hope all of you are too champs!" Björnsson wrote on Instagram. He'll compete in his first exhibition match Jan. 16 in Dubai against the 217-pound Steven Ward. However, Björnsson weighed in at a whopping 344 pounds, placing him far above professional boxing's 200-pound benchmark for the heavyweight division.

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While many know Björnsson for Game of Thrones, it's his strongman work (and the size that comes with it) that first caught the attention of producers. The 6-foot-9 Björnsson 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).

While Björnsson weighed over 450 pounds when he accomplished that feat, he quickly began shedding weight while pursuing boxing. He's currently slated to take on another former World's Strongest Man (and the previous deadlift world record holder), Eddie Hall, in September. With Hall also currently tipping the scales at well over 300 pounds, the bout is being aptly billed as "the Heaviest Boxing Match in History."

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Source: Instagram