Demetrious Johnson suffered a shocking knockout loss in the second round of his ONE Championship flyweight title fight against Adriano Moraes on Wednesday night in Singapore.

Johnson is considered to be one of the best mixed martial arts fighters in any company. But he appeared to be taken by surprise when Moraes delivered a knee to his face more than two minutes into the second round. Johnson was on the ground when he took the knee, fell backward and Moraes capitalized for the win.

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"I have to go back home and look at the fight, see when I made mistakes," Johnson said after the fight, via ESPN. "Adriano is very long, big. It was hard trying to get to him. This is part of the game. You stay in this game long enough, this is bound to happen at some point, right?"

It was the first televised event for the Asian-based mixed martial arts promotion in the U.S.

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Johnson came into the fight with 30 career wins. He had been the flyweight champion in the UFC before he joined ONE. During his stretch as champion, he would defend his belt 11 times between 2013 and 2018.

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"This is a dream come true," Moares said, via MMA Fighting. "I’m really working hard every single day. I don’t have the words to describe this moment. We did it. I grew up watching DJ fighting. He’s a legend. I knew exactly his game. Me and my team did the perfect strategy to fight against him. I got to him with a good uppercut. I’m so excited."