MMA mourned the passing of one of the most important figures in the sport’s transition from niche attraction to mainstream event after news broke of Stephan Bonnar’s passing.

Bonnar, a competitor in the inaugural season of The Ultimate fighter, passed away on December 22 to what were reported as “heart complications,” with the UFC’s official website and social channels announcing Bonnar’s passing on Christmas Eve.

In a statement posted to the UFC website, UFC president Dana White paid tribute to Bonnar, whose epic battle in the light heavyweight final of The Ultimate Fighter helped kickstart interest in the UFC, and MMA overall.

Stephan Bonnar was one of the most important fighters to ever compete in the Octagon,” said White.

“His fight with Forrest Griffin changed the sport forever, and he will never be forgotten. The fans loved him, related to him and he always gave them his best. He will be missed.”

That bout between Bonnar and Griffin is widely considered the pivotal bout in the history of the UFC as the pair battled all the way to the final bell as they fought tooth and nail to earn a six-figure contract with the UFC.

In the end, it was Griffin who claimed the victory, but White and Lorenzo Fertitta were so impressed with Bonnar that they made the decision in the cage after the fight to also award Bonnar a UFC deal.

It was the perfect feel-good moment to cap off a gamechanging night of fights in Las Vegas. More seasons of TUF followed, then mainstream acceptance, as the sport of MMA emerged from the fringes to become an accepted part of the sporting landscape.

Bonnar’s contribution to the sport’s success will be remembered in that fight with Griffin, and he went on to have 14 more fights in the UFC Octagon, going 8-6 during that run. His final career bout saw him lose a split decision to Tito Ortiz at Bellator 131 in November 2014.

Bonnar then swapped the MMA cage for the wrestling ring, where he competed for a number of independent promotions, as well as two stints with Impact Wrestling. He kept his eye on his old sport, however, and called fights for the WEC, while also making appearances as a guest analyst on ESPN and Fox.

Photo credit: Stephan Bonnar/Instagram