Derik Santos, the trainer for former UFC world champion Vitor Belfort, is not convinced with the reason for Oscar De La Hoya's withdrawal.

This coming Saturday night, De La Hoya was scheduled to fight for the first time since 2008, in a boxing match against Belfort. The fight was going to headline a pay-per-view being produced the Triller app.

Last week, De La Hoya withdrew from the fight after revealing that he tested positive for COVID-19.

The former six division champion, who is fully vaccinated, shot a video from a hospital bed and posted it to social media.

De La Hoya explained that he was feeling very ill, but Santos is not fully convinced.

"I'm not trying to disrespect Oscar, I saw the video of Oscar, but if I'm being honest, I'm still skeptical. Something about it didn't seem right. The level of how bad it looked. I know you can still get COVID if you're double vaccinated, but it didn't seem right. Maybe he realized we were taking the fight seriously, I don't know," Santos told .

"As far as I know, their side didn't try to jump out and reschedule like others have, so yeah, I'm a little skeptical. I think he thought: 'what I have got myself into' - he even posted this. We were going in there to give him a very good boxing match. We were ready. If the man does have COVID then I wish him a good recovery, I'm just mildly skeptical."

De La Hoya was replaced by former undisputed heavyweight champion Evander Holyfield.

Holyfield, despite being 58-years-old and inactive since 2011, will hold a big size advantage over Belfort, who planned to fight De La Hoya at catch-weight of 185-pounds.