Romero, who was born in Cuba, set off a firestorm on social media when he asked in accented English, "What happened to you USA?"
His closing comment came under the most scrutiny, as he apparently said, "Go for Jesus, not for gay Jesus," or "Go for Jesus, not forget Jesus."
Romero's comments were quickly linked to Friday's Supreme Court ruling in favor of the constitutional right to same-sex marriage.
Fox Sports, which aired Romero's third-round knockout on Fox Sports 1, wrote on Twitter: "Yoel Romero beats Lyoto Machida and then proceeds to scold the United States for believing that #LoveAlwaysWins." The tweet was later removed from the Fox Sports account.
During a postfight news conference, Romero, whose fighting nickname is "Soldier of God," said his comments were taken out of context.
"First of all, I would like to apologize -- there was a misunderstanding," Romero said. "First of all, I'm a man of God and God is love. My expressions are always going to be about love. What I was trying to say was, 'Look for the American Dream.' There was a misunderstanding about gay marriage.
"God told Mary Magdalene, 'You're a prostitute. Go and don't sin anymore.' And he told her with love. Who am I to judge anybody? Even though I didn't refer to that, even though there was a misunderstanding, I will tell you guys something. God made man to be free. Anybody can do whatever they want. I wouldn't be the type of person to critique anybody. I've got to look at myself first. Be a better person. To be able to love people.
"I didn't refer to anybody. What I was trying to say, was, 'United States, thank you for giving me the American Dream.' There's no better country than this one because it is blessed by God. It's in the dollars that this country was made by Christian people. That means it's blessed by God."
Romero, 38, is a former two-time Olympic wrestler. He won a silver medal for the Cuban team in the 2000 Olympic Games. He now trains out of American Top Team in Coconut Creek, Florida.