Champ champ! Henry Cejudo becomes two-weight UFC world champion at UFC 238
Cejudo was up against it after a tough opening round that saw him dominated by Moraes, who appeared to be completely controlling the action.
But after some adjustments between rounds, Cejudo came back in the second round by closing the distance, forcing himself into boxing range and connecting consistently with Moraes.
And, as Cejudo piled on the pressure in the third round, Moraes visibly began to wilt as the momentum of the bout shifted dramatically in the American's favor.
And with the final seconds counting down in the third round, Cejudo rained down a barrage of ground strikes on an exhausted Moraes, forcing referee Marc Goddard to stop the action with nine seconds of the round remaining.
"I am the greatest combat athlete of all time!" roared Cejudo after his thrilling victory.
"I was fighting adversity. I sprained my left ankle [earlier in the week]. I couldn't do much, but I still wanted to fight. I taped it up and stuck to it.
"It was all desire. I knew Marlon was throwing a lot of power. And I knew that when you throw that much power, you're going to get burned.
"When I saw his demeanor change and he started to drop his arms, I knew it was time to eat."
Cejudo's historic victory made him only the fourth fighter - after Conor McGregor, Daniel Cormier and Amanda Nunes - to holds two titles simultaneously in the UFC, and made good on his promise to prove his worth as a genuine pound-for-pound great.
And the first man to achieve that feat sent his congratulations on social media, as McGregor tweeted: "Congratulations Henry Cejudo! Welcome to the club."