Sergio Moraes is one of several MMA stars to contract COVID-19, and he says it was the toughest opponent he’s ever faced.

Consider he’s battled the likes of Kamaru Usman, Neil Magny, and James Krause, that’s saying something.

“Man, it’s very difficult,” Moraes told MMA Fighting of his battle with the virus. “I never had such an aggressive opponent… I went to Sao Paulo to take care of my parents and they ended up taking care of me.”

Moraes says he was shocked by the affect that the virus had on him, given that he’s a lifelong athlete. The shortness of breath he experienced, he says, was particularly difficult to cope with.

“The first four or five days, my doctor called and asked me to put on a mask and walk around the block to see if I would experience shortness of breath,” Moraes said. “I laughed. ‘Are you crazy? I’m an athlete my entire life, I have this disease for four days and you’re talking shortness of breath? You’re crazy.’ I hang up the phone, changed my clothes. I was already breathing heavy when I walked up the stairs. ‘My God, what is this?’ Man, I was so out of breath I had to sit down. I didn’t even walk around the block [laughs].

“I don’t think the media even says everything this disease causes,” Moraes added. “For some moments, if I know where was the off switch, ‘enough, no more,’ I would have pressed it. Man, it dominates you in such a way. The medicine are strong, you don’t want to eat and drink anything because of them. It really affects you. I was very concerned… Your hands are tied. You have to be strong, but you can’t.”

Thankfully, Sergio Moraes is now on the mend. While he’s no longer a member of the UFC roster, he’s hoping to get back to grappling competition once the coronavirus pandemic subsides.

This article first appeared on BJPENN.com on 5/6/2020.