"China's biggest exports..... Plastic and Covid...." he wrote.
The tweet was reminiscent of COVID times when President Donald Trump labeled the illness "the China Virus" and Xenophobia was at an all-time high.
It's timing seemed out and out of place, even for Strickland.
Song Yadong calls out Sean Strickland for 'baseless stereotypes'
But UFC fan favorite, Song Yadong, wasn't going to let the champ get away with insulting his home country. And he did it with the class Yadong is known for.
"Hey champ, I respect your skills as a fighter, but we should be talking facts, not baseless stereotypes," Yadong wrote. "As athletes, we ought to focus on what we know best and avoid making unfounded comments. Let's set a good example, alright?"
Strickland has been talking a lot lately about trash talk and the limits fighters should abide to. But hasn't stopped his own line of controversial statements and thoughts.
Yadong is gearing up to fight former bantamweight champion Petr Yan at UFC 299 in March. Strickland will face Dricus Du Plessis for his first tile defense at UFC 297.