Stephan Bonnar was among the most popular fighters in the promotion’s fledgling years

The UFC has announced the death of former fighter Stephan Bonnar, a man credited with helping to propel the promotion and the sport of MMA into the mainstream. Bonnar died on Thursday at the age of 45 as a result of “presumed heart complications,” the UFC said in a statement issued on Saturday.

“Stephan Bonnar was one of the most important fighters to ever compete in the Octagon,” said UFC president Dana 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.”

Bonnar was a competitor on the first series of ‘The Ultimate Fighter’ in 2005, a reality TV show in which fighters live and train in rival camps before facing off with each other.

Bonnar lost the light-heavyweight final against Forrest Griffin via decision, but the pair produced a contest hailed as among the greatest ever seen inside the cage.

The bout was inducted into the Fight Wing of the UFC Hall of Fame in 2013, and has been credited with “saving” the UFC by ensuring another season of TUF and introducing the sport to a new generation of fans.

Nicknamed ‘The American Psycho’, Bonnar fought 15 times for the UFC, earning eight wins and suffering seven losses. He faced iconic names such as Jon Jones, Mark Coleman, Anderson Silva, and Rashad Evans.

After his defeat to Brazilian icon Silva in his last UFC bout in October 2012, Bonnar went on to compete once more under the Bellator MMA banner in 2014, suffering a split decision defeat to Tito Ortiz.

His professional MMA record read 15 wins and nine losses in 24 visits to the cage.

Among the many figures in MMA to pay tribute to the Indiana-born Bonnar was longtime UFC pundit Joe Rogan, who described him as “a real legend.”

“RIP to one of the most important figures in the explosion of MMA,” wrote Rogan in a message shared on Instagram. “You will not be forgotten.”

Bonnar had a stint in wrestling following his retirement from MMA, and was a cornerman for fellow veteran fighter Diego Sanchez in 2020.

Bonnar suffered personal setbacks in recent years, not least the destruction of his Las Vegas home in a fire in April.

He also made headlines during the Covid-19 pandemic with social media posts about being required to wear a mask, as well as his position on a supposed crackdown on freedom of speech.

Bonnar is survived by his wife Andrea and their son Griffin Brandon.