Brazilian martial artist Anderson Silva has broken his shin, in possibly one of the most gruesome injuries caught on camera.
The 38-year-old, who is regarded as one of the greatest mixed martial arts fighters of all time, was competing at the Ultimate Fighting Championship in Las Vegas on Saturday night (US time).
Footage of the fight showed Silva's left shin bend grotesquely while he landed a kick on American Chris Weidman's left leg one minute 16 seconds into the round.
While it happened too quickly for the thousands of spectators at the stadium to witness live, there was a collective gasp of horror as the replay was shown.
Matt Erickson from MMAjunkie.com described the injury as "one of the most gruesome breaks in UFC history".
"And the questions immediately began about that being the end of a legendary MMA career," Erickson wrote.
A UFC orthopaedic surgeon said Silva had broken his tibia and fibula in the lower part of his left leg, the Daily Mail reported.
He underwent emergency surgery, but recovery could take up to six months, the UFC said in a statement.
Champion Weidman remained humble - if not a little bit guilty - about his victory.
"We trained checking the kick a lot. The idea is to pull your leg and for their shin to land at the knee. That's exactly what I did, and I felt his leg go right away," he said.
"There's no real excitement in a fight finishing like that, because you never want to see anyone get hurt like that."
Before losing to Weidman in July, Silva had been undefeated in the UFC "Octagon". Nicknamed The Spider, the loss took his career MMA record to 33-6.
Should Oscar Pistorius be allowed to compete again?