Bad news ... the UFC's legendary Octagon girls will NOT be working the event.

Good news ... we're told the Corona Girls will handle ring card duties instead -- and they ain't no slouches!

Here's the deal ... Corona won the bid to become the official beer of the fight -- which means they get prime in-ring promotion, which includes the beautiful women holding the ring cards.

So, what will the Octagon girls be doing on August 26? Hustlin' baby!

We spoke with Arianny Celeste, who says she'll be hosting a fight party in Miami ... and, shocker, she's rooting for Conor.