I read that he's the one fighter USDA has tested the most.
Source? Costa said Romero was just trying to buy more training time.
https://www.mmamania.com/2018/8/30/...msy-excuse-yoel-romero-think-hes-stalling-mma
“I think he’s stalling, he wants more time to train,” Costa told
Combate (via
Sherdog). “When the UFC sent him the contract, he knew the fight would be in November, otherwise they wouldn’t send it. He knows it’s going to be a tough fight, everyone in the weight class knows how it is when you fight me. He doesn’t want to risk his health, especially a 41-year-old man who’s probably thinking about retiring.”