UFC Hall Of Famer Stephan Bonnar Dead At 45

Stephan Bonnar passed away three days before Christmas Day. He was 45.

On Saturday, the UFC announced on its website that the UFC Hall of Famer died Thursday due to "presumed heart complications."

"The UFC family is saddened by the tragic passing of UFC Hall of Famer Stephan Bonnar Thursday from presumed heart complications while at work," the announcement read.

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

The UFC also sent its condolences to Bonnar's family and friends. No other detail about his death has been released as of this writing.

Bonnar introduced himself to UFC fans on the first season of the reality competition show "The Ultimate Fighter" in 2005. He teamed up with Griffin in the finale to produce one of the greatest fights of all time. Bonnar later earned a place in the UFC Hall of Fame's fight wing.

"I knew it was a good fight during the fight," Bonnar said of the epic three-rounder. "It hit me when everyone started stomping their feet and it felt like the whole place was shaking. And that was in the second round. I was like 'oooh, this must be good.'"

The Griffin-Bonnar fight reportedly saved the UFC and led to another season of "TUF," even introducing the sport to a new generation of fans.

"Everything changed," Bonnar said. "I didn't think I'd have a UFC career. It was just a little hobby I was doing, so it changed everything. Almost overnight, I became like a celebrity. Everywhere I went, someone would recognize me, even in obscure places. I was traveling with TapouT and we were in a small town. I was jogging and someone in a pickup was going 'Hey Bonnar.' And everywhere you go, someone knows who you are. It was wild."

Bonnar faced Griffin (for the second time), Jon Jones, Rashad Evans, Mark Coleman, Anderson Silva and Tito Ortiz before ending his career with a 17-9 record.

"It was kind of a little lesson," Bonnar said of his seminal fight with Griffin. "If you never quit, you really can't fail. That was the perfect example of that. Give it everything you've got and something good will come out of it."

Just days before his death, Bonnar promoted an upcoming fight in February titled "Fights of Fury" via his Instagram account.

"Rip, UFC legend," one fan commented on his post.

Another added, "No way he passed away. He just posted this 3 days ago, and now he's dead. Rip."

"RIP legend... THIS ONE HURTS!" a third fan wrote.

"His fight with Forrest Griffin made me a fan of UFC and, in my opinion, put the sport on the map," a fourth supporter wrote.