Although Nick Diaz vacated his Strikeforce welterweight title to swim in Georges St-Pierre’s Octagon pond, it appears their UFC 137 showdown is being promoted as a ‘Champion vs. Champion’ matchup – per the card’s official event poster.

If that’s the case, the 170-pound TITLE UNIFICATION bout takes place October 29th inside the Mandalay Bay Events Center in Las Vegas, Nevada. GSP defends his crown against Diaz in the night’s featured attraction.

A critical shootout between BJ Penn and Carlos Condit will co-headline the pay-per-view broadcast, but that’s not depicted in the billboard.

Here are the athletes slated to appear in the show:

Preliminary Bouts:

Dannny Downes vs. Ramsey Nijem

Eliot Marshall vs. Brandon Vera

Jeff Curran vs. Scott Jorgensen

Tim Credeur vs. Brad Tavares

Bart Palaszewski vs. Tyson Griffin

Hatsu Hioki vs. George Roop

Main Bouts:

(Pay-Per-View 9PM ET/6PM PT)

Dennis Siver vs. Donald Cerrone

Roy Nelson vs. Mirko “Cro Cop” Filipovic

Matt Mitrione vs. Cheick Kongo

Carlos Condit vs. BJ Penn

Nick Diaz vs. Georges St-Pierre (UFC Welterweight Champion)