UFC light heavyweight champion Jon Jones and Daniel Cormier squared off today for a photo opportunity to promote their UFC 178 title bout, but instead began round one of their fight (video above). As flash bulbs went off around them, Jones walked across the stage and got right in Cormier's face.

The two-time Olympian did not appreciate the champ's posturing and grabbed him by the neck to push him away roughly. Jones responded by firing a punch at Cormier and storming the challenger.

The stage's backdrop got torn down as the fighters tumbled off stage. Jones and Cormier have bantered for years and their title fight has been heavily anticipated by fans since before Cormier even dropped down from heavyweight, two fights ago.

No report yet on any injuries that may have resulted from the brawl (Cormier and Jones both are already injured, heading into their September contest), or if the UFC will take any disciplinary action against either or both men. We will keep you posted as the story develops.

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