The enemy was incredibly fast.  None of Obi-Wan's training had prepared him to deal with an opponent like this.  They hammered and spun at each other relentlessly, moving back and forth along the core's edge.  Although Obi-Was wasn't certain that his Master was dead, he tried to steer his opponents away from the area where Qui-Gon lay motionless on the floor, his lightsaber resting a short distance from his fingertips.  Obi-Wan slashed through the handle of his opponent's weapon deactivating one of the blades, but the black-clad figure held tight to his own lightwaber's still-operating half and continued fighting.