UFC Hall of Famer Stephan Bonnar died on Thursday, the promotion announced. He was 45 years old.
The UFC reported Bonnar, who most notably fought Forrest Griffin in the finals of the first season of “The Ultimate Fighter” in 2005, died of presumed heart complications while at work.
“Stephan Bonnar was one of the most important fighters to ever compete in the Octagon,” UFC President Dana White said in a statement.
“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, who once didn’t believe he would have a career as a UFC fighter, said “everything changed” after his fight with Griffin.
“Almost overnight, I became like a celebrity. Everywhere I went, someone would recognize me, even in obscure places,” Bonnar said.
During his career, the Indiana native battled future Hall of Famers Rashad Evans, Mark Coleman, Anderson Silva, and Tito Ortiz.
Bonnar finished his career with 15 wins in 24 fights before he was inducted into the UFC Hall of Fame in 2013.
“We lost a legend,” UFC commentator Joe Rogan said in a heartfelt post on Instagram, saying Bonnar will “never be forgotten.”
“RIP to the American Pyscho, Stephan Bonnar. I remember watching him and Anderson Silva,” tweeted internet celebrity turned boxer Jake Paul.
UFC fighter Renato Moicano tweeted his condolences, calling Bonnar’s death “a sad year for the UFC community.”
“Stephan Bonner a key piece to the growth of our sport,” retired UFC star Frankie Edgar said. “I remember watching him and Forest battling it out and thinking, I gotta try this out. RIP to a true pioneer!”