Simpson was out in Las Vegas when a photog asked him about Caitlyn's recent comments. At first, he said he's never met Caitlyn and claims he barely knew Bruce, despite the fact they vacationed together. Then he started jabbing.
Watch ... O.J. seems to think his comment is lighthearted, or even a joke.
We're guessing Caitlyn won't be laughing about it, and we're sure, after seeing this ... there's bad blood between the old friends.
Btw, O.J. also makes it clear he's loving the Vegas life.